http://www.fudzilla.com/graphics/graphics/ati-also-wins-macpro-deal
This might be a concern for CS5 users, if the hardware MPE continues to be nVidia only.
I also noticed that the Fermi line of Quadro cards have been announced.
I'm not sure that this means you can't buy an NVIDIA card...just that Apple isn't going to offer one in a stock model.
As far as Fermi is concerned...Adobe has said it will update the list of eligible cards as new models arrive and are tested.