I'd personally like to see the 8800GTX or the 8800GT and nothing from ATI. Besides the fact that the HD 2900xt is now being EOL'd and being replaced by a newer 55nm part, it is loud and hot and is ourperformed by the 8800GTX.
Seeing that Nvidia can't write Mac OS X drivers worth even a tenth of a s**t, I'd like to see Apple kick Nvidia to the curb and stick with ATI, which has much more stable drivers on the OS X platform.
There have been NO END of problems with the Nvidia 8600 mobile chipsets in the Macbook Pros due to driver problems. People playing Second Life, WoW, and other games have had crashes, glitching, and so on, and none of these problems have been fully fixed yet.
Please, oh please let Apple stick with ATI cards. My X1900XT in my Mac Pro is *ROCK SOLID*, as is the X1600 chipset in my rev 1 Macbook Pro. There have been minor instability issues in the aluminum iMacs, but they have been fixed as far as I know. Nvidia has yet to fix their drivers.
-Z