The purpose of this thread appears to be that a computer that was hugely overpowered when it was new is still sufficient to run current games two years later at an outdated resolution. As far as I'm concerned, the OP is 100% incorrect. I've been using a 1920x1200 monitor for over 5 years, and my last video card (an HD5870) was insufficient to run Skyrim at ultra settings with mods installed because of VRAM limitations (which neither crossfire nor SLI would address). I upgraded to a GTX 680 and now I can run everything (Skyrim, BF3, Batman, Crysis, Alan Wake, etc.) at ultra settings at 1920x1200 with a combination of AF and AA at playable FPS levels.
For mid-level gaming, of course you don't need the latest or greatest graphics card; you never have. But if you're interested in running multi-monitor or super-high-resolution monitors with all the eye candy turned up to get the absolute maximum IQ out of today's games, an SLI GTX 460 rig simply will not cut it. At the enthusiast level, there's nothing available that counts as overkill, which is why you see people flaunting their 6 GHz overclocks and quadfire 7970 setups feeding 6 monitors in eyefinity.