I played Metro 2033 on Very High with AAA last night and got an average of 50fps (granted, it usually drops to 30fps when I'm on the surface) with my HD 6870. I average 45 in Crysis 2 on Ultra, and around 50 in Crysis 1 on Very High with no MSAA. I agree that there are better cards for 900p, and good luck if you're shooting for 60fps in all games on Ultra with MSAA. The GTX 680 can't even manage that. A more realistic goal would be 45fps in all games with or without MSAA. A GTX 660 or HD 7870 can handle that.
Also, the Crysis 3 Open Beta started today, so fire up Origin and go to Demos and see how it runs for you! Well, provided you have a DX11 card - I think it's exclusively DX11.