nVidia SLI in 2010
Okay this seems to be following me everywhere I go in the PC gaming world so I'm going to address this. The new nVidia graphics cards scale extremely well in SLI. That's the news everyone is raving about. As is the nature of news the old information seems to get lost in the wind. By running SLI, you are running two graphics cards at once. It's a simple fact that people don't seem to get.
Not every developer codes their engine for proper multi-gpu scaling or even multi-gpu support. Some Starcraft 2 players are still smoothing out rough edges after the patch that fixed stuttering and slow down. The upcoming Final Fantasy XIV does NOT support SLI, at all. The recent MMO All-Points Bulletin does not support SLI either. This is not "the list" but it is merely an example of games still being released today that don't support SLI. Let's not even travel backwards to games that don't support SLI or don't scale well.
In addition, you're looking at about a twenty degree idle temp increase (comparing 2x460s to 1x480) and increased power consumption. I think this is a solid step towards making SLI reliable but if you're thinking about the cost savings then we're not there yet. This especially rings true to me someone like me who is only looking forward to FFXIV as his main title for 2010 while he takes Starcraft breaks and catches up on his giant Steam library of unfinished titles.
If you're the kind of guy that says, "I want to play Crysis 2 on Ultra and laugh at the people who spent $100 more than me on reliable across the band power," (yeah I just made an auto reference) then by all means go for it. Just get real used to play Crysis 2's 5 hour campaign over and over because all you're gaming addict friends are going to laugh right back when all your GPU-muscle suddenly disappears in the games everyone is playing.
The achievement nVidia has accomplished is destroyed any reason to think about a Crossfire setup. If you're looking for a power house setup, you're still looking at the GeForce 480 or the Radeon 5870.
NOTE: I'm too lazy to put a pic in, imagine something creative...