Bitcoins: The Future?

[MachineGhost]

For all the talk of alternative monetary systems, I would betcha that P2P anarcho-crypto Bitcoins will pwn them all in a few years.  "Unanticipated", disruptive change is so very typical of what happens to politicians, academics and pundits stuck on fighting the last war and who can't see their way out from between their two butt cheeks.  Because of how dependent the HBPP is on debt-based money issued from or supported by the aforementioned cretins, it doesn't seem like a bad idea to hedge a little bit by puchasing some Bitcoins.

What we have here is radically different from the current system where money creation is based on debt, politically motivated, surrounded by secrecy, inflationary, unilateralist, colonialist, and exploitative of powerless nations, etc. The flaws in the design of modern currency are at the roots of the social and ecological disasters we face today. Alternative currencies in general hold the promise of a way out, and the emergence of a vibrant Bitcoin economy in particular is one of the most interesting developments in recent times.

http://www.aljazeera.com/indepth/opinio ... 31677.html

[craigr]

If Bitcoins ever catches on seriously the governments will conspire to shut it all down, sadly.

I'd love to see an anonymous electronic currency take hold, but governments seem to be going towards fully traceable money. In fact, I would not be surprised to see RFID in all US dollars the next 20 years. That would enable tracking from the ATM dispenser to the store where you buy goods to the bank where it is then deposited.

Meaning when you remove money from the ATM the serial numbers of the bills will be tagged to you as the withdrawer. When you go to a store the money could be scanned as part of the transaction (maybe guised as "counterfeit" protection) and the serial number then moves to the store. The store then deposits the money, it is scanned, and the serial number goes back to the bank.

If you hand money to someone privately and they deposit it, the records will know you had it first.

Or how about you do something to offend the political elite and they cancel your serial numbers on your money so nobody would accept it because the store scanner says it's invalid?

Once that happens, it will allow them to close the loop on anonymous transactions totally.

Just my pet conspiracy of how I think this will all go down after writing a white paper on RFID security vulnerabilities and getting glimpses into how the technology is being sold.

[Storm]

Craig, I'm not sure how exactly the authorities could shut Bitcoin down.  That would be like trying to shut Bittorrent down (the protocol, not an individual tracker).  Because it is decentralized there is really no single place to shutdown Bitcoin.  They would have to somehow make running the client illegal in every country in the world, and enforce that.

Personally I'm just holding onto mine as a speculative investment.  Today they are worth around $11.50 USD each, however, BTC is divisible down to 8 decimal places.  If everyone started using BTC the price increase in USD could be astronomical.

[craigr]

Craig, I'm not sure how exactly the authorities could shut Bitcoin down.  That would be like trying to shut Bittorrent down (the protocol, not an individual tracker).  Because it is decentralized there is really no single place to shutdown Bitcoin.  They would have to somehow make running the client illegal in every country in the world, and enforce that.

Yes I understand. I am just suspicious that where there is a bureaucratic will, there is a bureaucratic way to make it happen. I hope it doesn't happen, but governments like controlling money. When you control money, you can better control people.

Personally I'm just holding onto mine as a speculative investment.  Today they are worth around $11.50 USD each, however, BTC is divisible down to 8 decimal places.  If everyone started using BTC the price increase in USD could be astronomical.

I think more than investment value is the personal liberty/privacy that is the real value to me. I am keeping an eye on how it all works out as it's kind of frontier town now. But hopefully yes we'll see it take hold to the point where no central authority can control it. Certainly the Internet has shown that controlling decentralized systems is much harder than governments had thought it would be.

[Storm]

The biggest issue I've seen so far preventing widespread adoption is that it requires about 10 minutes for the network to confirm a transaction.  This makes most point of sale applications a non-starter.  No store wants to trust you that the payment will come through in 10 minutes, and no customer wants to stand there waiting for the transaction to go through.  What this means is that there will have to be some intermediary way to store Bitcoin credit that has instantaneous transactions; something like Dwolla or Square perhaps, and these are susceptible to government shutdown.

I found it quite interesting when I heard that in Africa more people have mobile phones than bank accounts.  They have a mobile payment system called M-Pesa that people use like money.  This is fascinating to me as it seems like these mobile payment networks could take the place of money almost completely.

http://news.bbc.co.uk/2/hi/8194241.stm

[MachineGhost]

I'd love to see an anonymous electronic currency take hold, but governments seem to be going towards fully traceable money. In fact, I would not be surprised to see RFID in all US dollars the next 20 years. That would enable tracking from the ATM dispenser to the store where you buy goods to the bank where it is then deposited.

But Bitcoins isn't anonymous as it is fully transparant with a full chain of record for all transactions.

[Storm]

I'd love to see an anonymous electronic currency take hold, but governments seem to be going towards fully traceable money. In fact, I would not be surprised to see RFID in all US dollars the next 20 years. That would enable tracking from the ATM dispenser to the store where you buy goods to the bank where it is then deposited.

But Bitcoins isn't anonymous as it is fully transparant with a full chain of record for all transactions.

Yes, MG, this is a very good point.  Bitcoin was never designed for anonymity.  You can trace transactions because they are all recorded in the public blockchain.  A blockchain is just a ledger that basically says "wallet ABC sent 0.50BTC to wallet XYZ."  What makes Bitcoin secure is that the blockchain is cryptographically hashed with very strong algorithms and at least 50.1% of the computers running in the Bitcoin network have to agree on each block before it becomes part of the permanent blockchain.

However, that being said, anyone can generate new wallet addresses, so it is possible for someone to generate millions of wallets that they all control and move Bitcoins around between them so much that it is difficult to trace where any money really went.

[MachineGhost]

I've been playing around with the various mining softwares.  It's seems pretty clear to me that the costs to mine Bitcoins don't make economic sense anymore unless you're willing to risk buying six Radeon 5850 graphics cards.  For about $720+, you could make it back in 6 months if you're lucky, but mining compensation is going to drop by 50% by the end of the year as the difficulty increases.  A lot of mining liquidations or consolidations may have to happen.

Nonetheless, I find it sort of fascinating that all perceived monetary value is essentially about converting energy into something else or into a kind of storage or exchange mechanism.  Even gold is first made inside a supernova.  As humans, we all take a sun's energy and process it.  That is what distinguishes us from all the other animals.

I suspect the value of Bitcoins may rise and fall along with the stock market or general economy.

Edit: It's not economical in the 4 months remaining even with 6 graphics cards:

Power cost per time frame: 623.72 USD
Revenue per time frame: 1222.12 USD
      ... less power costs: 598.39 USD

Hardware break even: 287 days
Net profit first time frame: -753.61 USD

[herbgoat]

I too find this topic very interesting. Here is my take on it.

A few years back, I read a book called The History of Money by Jack Weatherford. It was a very good read and I think that a lot of the things that make a good currency fit Bitcoin well. I hadn't even heard of Bitcoin until I read about here so thanks to the OP.

From the best of my memory, I remember Weatherford talking in his book about early societies. They used things such as rice and other commodities. There were a couple main problems. The "money" would spoil (didn't have a long enough shelf life), it wasn't scarce enough (you could take a walk down the trail picking up cool rocks and you would be rich!), or it was to bulky to carry around with you.

Enter Gold and other metallic coins. It doesn't spoil, it's scarce/hard to find, and it's small enough to fit in your pocket. Those were the main reasons I remember him saying that Gold was adopted as an early currency.

Of course now, we have electronic money. Credit cards, wire transfers, ACH transactions. The problem is that because all of the governments in the world with fiat currency just keep printing more and more, I think the money supply is losing it's scarcity value (and causing inflation). This is causing people worldwide to start losing faith in the fiat currencies. People are realizing that fiat currency is no longer a good store of value so naturally they are looking elsewhere. Gold is the obvious first choice. It's been around forever, it's scarce, it doesn't spoil, and you can carry enough with you to transact business although right now, you'd probably have a hard time actually spending it (at the 7-11).

Now compare it with Bitcoin. It doesn't spoil, it's scarce (the algorithm only allows for 21,000,000 Bitcoins) and cannot be inflated, and it's electronic so you can conceivably carry your entire life savings in your pocket. Now imagine you're trying to conduct business over the internet halfway around the world, which would you choose? Gold or Bitcoin? Bitcoin has the added benefit of ease of transfer across long distance.

I have read through several FAQ's and websites on Bitcoin now and most of my serious questions have been answered. I'm with Craigr in that I think the most serious threat is governments trying to stop its citizens from using it. It's true that it would be virtually impossible to shut down the Bitcoin P2P network. However, individual governments could conceivably pass legislation to make it illegal to engage in a Bitcoin transaction. It might be hard to enforce, but the law would still discourage enough people to slow or halt the adoption of the new currency. They'll probably name the bill something like "Protecting citizens from drugs and Bitcoin" and a large media campaign will be sponsored by the large banks.

One last thought is about what Harry Browne said about stashing some gold in a vault in a foreign country so that you'd have a place to go in case of domestic turmoil. Now imagine replacing that strategy with just having a Bitcoin wallet with enough money to get started in another land. You could go anywhere in the world and theoretically convert your Bitcoins to local dollars. You would not be locked into going to the country that you have your Gold stashed, you could go anywhere! As an added bonus, you could access it instantly in your home country if you needed it! That's good stuff right there.

I'm thinking about buying some Bitcoins but I have to convince my wife first. I don't know if that will be possible. Wish me luck!

[Storm]

I've been playing around with the various mining softwares.  It's seems pretty clear to me that the costs to mine Bitcoins don't make economic sense anymore unless you're willing to risk buying six Radeon 5850 graphics cards.  For about $720+, you could make it back in 6 months if you're lucky, but mining compensation is going to drop by 50% by the end of the year as the difficulty increases.  A lot of mining liquidations or consolidations may have to happen.

I bought a Radeon 6990 over a year ago and have since then mined about 150 BTC.  I did stop mining for about 6 months though, when BTC was only $3 or so it cost me more in electricity to mine a coin, so I decided to stop for a while.

As the difficulty doubles this year, I think we should see the value of BTC increase to compensate the miners.  After all, it does seem to reach equilibrium with electricity prices unless the demand increases beyond supply, which is what we seem to be experiencing now.

[Storm]

One last thought is about what Harry Browne said about stashing some gold in a vault in a foreign country so that you'd have a place to go in case of domestic turmoil. Now imagine replacing that strategy with just having a Bitcoin wallet with enough money to get started in another land. You could go anywhere in the world and theoretically convert your Bitcoins to local dollars. You would not be locked into going to the country that you have your Gold stashed, you could go anywhere! As an added bonus, you could access it instantly in your home country if you needed it! That's good stuff right there.

I'm thinking about buying some Bitcoins but I have to convince my wife first. I don't know if that will be possible. Wish me luck!

Herbgoat, some very good comments there.  As a currency, Bitcoin is pretty good, however, there is one problem that I think it has, that is the forced deflation caused by lost wallets.  For example, a lot of people started mining Bitcoin when it first was released, and it didn't require a lot of expensive hardware.  You could mine 100-200 coins very easily in an afternoon just running it on your desktop computer.  Surely some of these people sold their coins for a tidy profit, but I'd be willing to bet that a lot of them just forgot about them, uninstalled Bitcoin, and those coins will never be spent.

If we were still using gold as currency, I'm not sure exactly what would happen if all mining operations ceased and no new gold was ever created.  People hoarding gold, or just plain losing coins, would cause loss of money supply.  We might end up in a scenario where one Bitcoin is worth millions of dollars, or they might just become so scarce that nobody uses them any more.

One thing I would caution you about buying them is that you might consider slowly averaging in.  Earlier this year you could buy them below $3 each.  I remember reading a story about somebody converting their life savings into Bitcoins when they were $30 each, and they probably lost a lot of money.  It is a speculative currency, after all.

If you do buy some as an investment, or a safe haven, I would recommend reading up about offline wallets.  It is possible to make a very secure offline wallet on a USB thumb drive and send your Bitcoins there.  That way, nobody will be able to steal your Bitcoins by hacking your computer.  Some people have gone to great lengths to secure their offline wallets.

For example, you can create an offline wallet, seal it in a section of PVC pipe, and bury it in your back yard somewhere.  Bury two copies in case one of them fails or goes bad.  Prior to burying the offline wallet, you can print a list of wallet addresses out and keep it handy, so then you can continue to send new deposits to this offline wallet.  Because of the nature of the blockchain, you never need to bring your offline wallet online to receive funds.  Those transfers are recorded in the blockchain permanently, so even 10 years from now, if you need to spend your money, all you have to do is bring up your offline wallet, let the blockchain catch up, and you can spend your money.

Good luck!

[herbgoat]

Surely some of these people sold their coins for a tidy profit, but I'd be willing to bet that a lot of them just forgot about them, uninstalled Bitcoin, and those coins will never be spent.

If we were still using gold as currency, I'm not sure exactly what would happen if all mining operations ceased and no new gold was ever created.  People hoarding gold, or just plain losing coins, would cause loss of money supply.  We might end up in a scenario where one Bitcoin is worth millions of dollars, or they might just become so scarce that nobody uses them any more.

Storm,

One of the things I read in an FAQ somewhere addressed the issue of Bitcoin's being lost and the number of available units decreasing over time. Right now, the current P2P client software goes to 8 decimal places so you can buy/sell .00000001 of a Bitcoin. Because it is a digital currency, it is possible to add an infinite number of decimal places. Even if there were only 1 Bitcoin left, you could simply divide it to the number of decimal places needed to work with the current currency exchange rates and pricing. That 1 Bitcoin may be worth $4 trillion USD but you could buy a hamburger for 0.0000000025 of a Bitcoin. Of course, society would probably create an easier name for the smaller units so you could just say, "that'll be 2 and half supermicrobits" or whatever.

Thanks for your advice about averaging in. I agree that's probably a good idea. This thing is so new and volatile who knows what could happen. I think in time this concept or one similar to it will succeed. It might take a really long time for many people to warm up to the idea though. It might not be Bitcoin but the next iteration that makes it mainstream. It will be interesting to watch and see what happens.

[MachineGhost]

I bought a Radeon 6990 over a year ago and have since then mined about 150 BTC.  I did stop mining for about 6 months though, when BTC was only $3 or so it cost me more in electricity to mine a coin, so I decided to stop for a while.

Why did you choose the 6990 over the 5970?  From what I calculate, the cost per Mhash/s ratio score is 1.37 ($525/772) for the former vs 2.35 ($300/704) for the latter and theres also more wattage requirements for the former.

My 9800GT is supposed to be capable of 30 Mhash/s but because native CUDA support is virtually nonexistent in the miners, it gets only 21-26 Mhash/s before the GPU drops 50% of usage for a while before resuming at 100% usage, then repeating.  Very annoying.  I sure wish I took Bitcoins more seriously at least a year ago when GPU mining was more economical.

[MachineGhost]

If you do buy some as an investment, or a safe haven, I would recommend reading up about offline wallets.  It is possible to make a very secure offline wallet on a USB thumb drive and send your Bitcoins there.  That way, nobody will be able to steal your Bitcoins by hacking your computer.  Some people have gone to great lengths to secure their offline wallets.

That's a pretty good idea.  I'm quite partial to the Xporter XT Boost line of USB drives as they are very rugged and sturdy and will even survive a washing machine cycle.

to receive funds.  Those transfers are recorded in the blockchain permanently, so even 10 years from now, if you need to spend your money, all you have to do is bring up your offline wallet, let the blockchain catch up, and you can spend your money.

It took a very long time to download the entire block chain.  It seems to slow down horribly on the more recent transactions (last 1-2 weeks or so).  What's up with that?

[Storm]

I bought a Radeon 6990 over a year ago and have since then mined about 150 BTC.  I did stop mining for about 6 months though, when BTC was only $3 or so it cost me more in electricity to mine a coin, so I decided to stop for a while.

Why did you choose the 6990 over the 5970?  From what I calculate, the cost per Mhash/s ratio score is 1.37 ($525/772) for the former vs 2.35 ($300/704) for the latter and theres also more wattage requirements for the former.

My 9800GT is supposed to be capable of 30 Mhash/s but because native CUDA support is virtually nonexistent in the miners, it gets only 21-26 Mhash/s before the GPU drops 50% of usage for a while before resuming at 100% usage, then repeating.  Very annoying.  I sure wish I took Bitcoins more seriously at least a year ago when GPU mining was more economical.

Well, I chose the 6990 because I also use the computer for gaming, not just mining, and I didn't want to have to build one of those monster systems with 4 graphics cards in it.  The 6990 allows me to run 2 miners at once (it's really 2 cards in 1) and I can disable one miner for a couple of hours if I want to play a game.  Overall, the 6990 is more efficient power-wise, and I can mine 400 Mhash/sec. on each card for a total of 800 Mhash/sec.

If you're buying it just for mining, the 5850s are probably the cheapest $/Mhash.  Then, you need to worry about the logistics of sticking as many of them in a single computer as possible and keeping them cool.  I've seen some crazy setups: http://www.youtube.com/watch?v=eLt8Se3vVNg

I'm not really doing full fledged mining as a business.  I just wanted to generate a few hundred coins to hang onto for a few years and see if they're worth something some day.

[HB Reader]

Can anyone recommend a BitCoin Exchange?

I obtained a few last year, but haven't messed with them since Mt Gox got hacked last year.

[herbgoat]

I decided to give mining a try on my Nvidia GeForce GTS 450. I'm getting about 40 Mhash/s. I joined slush's pool. It's been going for about half an hour and my rig is already getting hot. Hmmm. maybe I'll just buy some coins. I'll let it go awhile so I can at least get my first withdrawal.

[Storm]

It took a very long time to download the entire block chain.  It seems to slow down horribly on the more recent transactions (last 1-2 weeks or so).  What's up with that?

The blockchain is pretty large - it's basically a ledger of every single Bitcoin transaction ever made, so it will continue to grow over time.  During periods of time where Bitcoin value is high and there is a lot of activity going on, the blockchain will grow larger.

I do believe the inventor(s?) of Bitcoin were pretty smart, because when asked if the blockchain would ever become unmanageable, they basically said that computer storage will grow fast enough that storing a 1TB blockchain in the year 2020 will be trivial.

Another alternative theory to the recent uptick in transaction volume and value is that Burning Man is happening soon and a bunch of people just wanted to buy drugs on Silk Road... 

[Storm]

I decided to give mining a try on my Nvidia GeForce GTS 450. I'm getting about 40 Mhash/s. I joined slush's pool. It's been going for about half an hour and my rig is already getting hot. Hmmm. maybe I'll just buy some coins. I'll let it go awhile so I can at least get my first withdrawal.

At 40 Mhash/second you are likely to get 0.02 Bitcoins per 24 hours mined, or about 24 cents a day.  My guess is that your power bill for leaving your computer running 24/7 will be more than that.

My computer can generate 800 Mhash/second at about half a kilowatt, which I pay about 18 cents per kilowatt hour for.  I have been averaging about .5 Bitcoin a day so basically it costs me $2.16 in electricity to make about $6 return.

[Storm]

Can anyone recommend a BitCoin Exchange?

I obtained a few last year, but haven't messed with them since Mt Gox got hacked last year.

I still use Mt. Gox.  They did get hacked, but I believe they learned from their mistakes and increased security significantly.  What's more, I tried other exchanges like TradeHill, who ripped me off for about $30 USD of Bitcoins (removed Dwolla as a transfer method, claimed they mailed a check which I never received, then wanted to charge me a $25 stop payment fee for a $30 check, then went out of business), and I still believe Mt. Gox is the most trustworthy because I have never heard of a customer getting ripped off.

Be careful with some of the other exchanges.  Mt. Gox has been around the longest and I do believe they are not in it to make a quick buck; I think they're in it for the long haul.

[HB Reader]

Be careful with some of the other exchanges.  Mt. Gox has been around the longest and I do believe they are not in it to make a quick buck; I think they're in it for the long haul.

Storm --

I did a few small transactions with them last year before they were attacked and didn't have any problems.  I guess I'll go ahead and try to re-establish my account with them.  Thanks for the quick reply.

[herbgoat]

This was just posted a few hours ago on youtube. It's video from a libertarian conference in New Hampshire. It's an hour long but I thoroughly enjoyed watching all of it. If you're interested in Bitcoin it's worth a watch.

http://www.youtube.com/watch?v=088le0gCh-0

[MachineGhost]

If you're buying it just for mining, the 5850s are probably the cheapest $/Mhash.  Then, you need to worry about the logistics of sticking as many of them in a single computer as possible and keeping them cool.  I've seen some crazy setups: http://www.youtube.com/watch?v=eLt8Se3vVNg

I didn't know the 6990 had two GPU's.  Does that hold true for the 5990 as well?

There are definitely issues to consider that weren't highlighted in any of the hardware guides.  Another reason I would favor the 5950/70 over the 59/6990 is the issue of power connectors.  Since each 5950/70 requires two 6-pin power connectors vs two 6-pin+8-pin power connectors for 59/6990, that effectively limits each 6x 6-pin capable power supply to driving 3 cards.  With a special case that can hold two such power supplies and a motherboard that supports 6 PCI-E slots, it becomes feasible to drive 6 cards in one machine.  I didn't go far enough to check into the 12v amp rail situation but if that was also a factor, it would require some incredibly expensive ($300+ each) power supplies.  It's really surprising how most power supplies are overpriced junk, either through excessive heat wastage or lack of power to the rails.

My 9800GT was hitting 103c (200F) at full GPU load while mining.  Since this was an older card, I had just assumed it was relatively normal and beefed up the case airflow and thats how the cookie crumbled for 5 years or so.  But last night I had a thought that maybe the card was throttling down to 50% GPU usage to prevent damage.  So I opened it up and put on some Arctic Silver Matrix, a thin spread on the GPU and a dab on each of the memory chips (on-top of the stock "paste" which looked and felt sort of like small gauze pads, WTF?).  Then, since there was about 20% left, I figured what the hell and just oozed all the rest out onto the GPU since the copper heat plate was larger than the GPU.  Now, the peak load is 70c (140F) max.  Wow, it is amazing I didn't burn the card out playing the occasional 3D game.  Now, the room is cooler and the A/C isn't working as hard.  The 9800GT is actually a RMA replacement for a 8800GT that died and which I now think had a similar overheating issue.  I'll be avoiding PNY in the future.

[MachineGhost]

My computer can generate 800 Mhash/second at about half a kilowatt, which I pay about 18 cents per kilowatt hour for.  I have been averaging about .5 Bitcoin a day so basically it costs me $2.16 in electricity to make about $6 return.

How can you run the 6990 in a regular system at a half a kilowatt?  If I added the 6990 to my system now, it would draw 243 watts for the mainboard+peripherals plus 375 watts for the 6990, 618 watts total, requiring a 750, 850 or 1000 watt power supply depending on 80PLUS certification or not.  I currently draw 375 watts total (with the 9800GT) using a regular 575 watt power supply @ 60% efficiency, so its right at the "power cliff".

According to http://bitcoinx.com/profit/index.php if you draw 750 watts to cover the 618 watts (80PLUS Bronze), pay .18/kilowatt hour and mine at 772 Mhash/s, you would only make a net $1.06 a day after spending $3.24 in electricity and earning $4.30 in revenue.  Even at an arguably 500 watts (80PLUS Platinum?), it shows only $2.14/day net.  Whose numbers are currently more accurate?

And are you solo mining or pool mining?  If pool, which pool?

[Storm]

My computer can generate 800 Mhash/second at about half a kilowatt, which I pay about 18 cents per kilowatt hour for.  I have been averaging about .5 Bitcoin a day so basically it costs me $2.16 in electricity to make about $6 return.

How can you run the 6990 in a regular system at a half a kilowatt?  If I added the 6990 to my system now, it would draw 243 watts for the mainboard+peripherals plus 375 watts for the 6990, 618 watts total, requiring a 750, 850 or 1000 watt power supply depending on 80PLUS certification or not.  I currently draw 375 watts total (with the 9800GT) using a regular 575 watt power supply @ 60% efficiency, so its right at the "power cliff".

According to http://bitcoinx.com/profit/index.php if you draw 750 watts to cover the 618 watts (80PLUS Bronze), pay .18/kilowatt hour and mine at 772 Mhash/s, you would only make a net $1.06 a day after spending $3.24 in electricity and earning $4.30 in revenue.  Even at an arguably 500 watts (80PLUS Platinum?), it shows only $2.14/day net.  Whose numbers are currently more accurate?

And are you solo mining or pool mining?  If pool, which pool?

You're right, I just checked my UPS which shows power draw and it is around 639 watts (with my 27" monitor - not sure how much of that is the monitor, which isn't normally on).  I was rounding to 500 watts.  I have an 80plus power supply, but I wasn't counting the loss.

http://www.newegg.com/Product/Product.a ... 6817139009

I guess one reason I don't count as much is because I leave the computer on all day regardless of whether it is mining or not. So mining is just adding about 350 watts to my normal usage.  The computer is a backup server for all the other laptops and devices, as well as a media server.  So, my net is much lower than originally anticipated.

I'm using deepbit.net as my pool.  They seem to be the most reliable (least downtime) out of the ones I've tried; admittedly I haven't tried a lot of pools (slush's and overclockers.net).

The Radeon 5970 and 5990 are both dual cards (5990 is clocked a little higher, I believe).  I think the 5850 is probably still around the best available in price per mhash/s.

You can reliably get around 350-375 Mhash/s per 58xx series GPU (double that for the 5970/5990) and probably around 400 Mhash/s for the 69xx series GPU (double that for 6990).

At the time I bought my 6990 the 5990s were completely sold out everywhere - I had to wait a month even for my 6990 to get in stock.  Miners were buying them up at a rapid rate.