After all the hype about 6970 beating the 580 by 30-40% (I even fell for it too) and coming back down to earth, I just ordered 2 6950s. I'm upgrading from a 460 1GB which was just a placeholder as I sold my 5870 2 months back before the 6870 released. I almost picked up SLI 570s, but then after thinking some more about it I changed my mind.
After using a 5870 for more than a good half year I feel having more video memory is more important than a slight performance increase. Not saying the 5870 is a bad card, that's not true. It's very fast, but sometimes that 1GB VRAM is it's achilles' heel.
I don't know about other people, but I play PC games for the better experience and higher quality graphics, otherwise I'd stick with a console. I missed out on having AA (both on 5870 and 460) but it looks like 8xAA and high resolution is one of the 6900s strong points, and I'm sure going to love it.