Getting ready to order a new gaming notebook (Sager) and am a bit confused as to video card choice. I am looking at the AMD 6990M vs. nVidia GTX 485 or GTX 580. I don't have to have the fastest, but I want to extend longevity well into the future. I am concerned about driver updates for the AMD/ATI card vs. the nVidia cards. Any reason to choose one over the other (other than $$)? My gaming is largely first person shooter new releases. Titles that I have played, when new, were COD Black Ops, Crysis 2, Portal 2.