It isn't just AH that I play though. World of Warcraft was taking my 8800 to low single digits in some cases at high detail settings. In a place where the 8800 did 10-15 frames per second, the 7800 was doing 1 frame every 5 to 10 seconds.
Basically, I want to get a card that will last a good while, at least as long as the 8800GT did. Because of that it should be a DX11 part, so really I think I am looking at the ATI 5850 or nVidia GTX 470.