It's going to take a hell of a lot more than one half assed console port of a game to get me to switch to nVidia.
I said when it comes time to upgrade I will go to NVIDIA. Its not like I am running down to the shop to buy NVIDIA because of RAGE.
The general experience I have had with ATI since I got a 5850 has been rather poor. There are some bugs in their drivers that I have had since day-1 of my 5850 that despite repeated forum posting, support emails, "Catalyst feedback" forms they refuse to fix.
I have done 3D/OpenGL and CUDA/OpenCL programming professionally on both ATI and NVIDIA hardware and NVIDIA beat them in every category I can think of except price. But when your products are superior to your competition you will of course sell your products at a higher price (just look at price gap between Intel and AMD).
The one thing I do credit AMD for is that they provide good documentation on how their chip sets are wired. Theoretically it is possible for anyone with the technical skill and time to write an alternative driver for AMD cards. NVIDIA keep their chip designs very secret.