Well, I am more than capable of playing just about any game on my PC. Halo runs great on my PC, but the game still sucks, and it still looks like ass IMO.
The problem is that although I have a fondness for RTS games, and Sim games, I really have distaste for FPS games, and I am not really interested in playing rehashes of RTS and Sim games that I played years ago. PC games just don't innovate. That's why I prefer my console games.
I still like to keep my computer up to date though, as I am a programmer, and my computer is about the only valuable thing I own. I am actually planning on doing a complete upgrade of my PC this winter though, involving a new case, new motherboard, new CPU, removal of most fans, addition of cathode lights, watercooling, and EL Wire, and 1GB of memory, and replacing my POS monitor with a nice LCD one. I was also thinking of replacing my aging video card with something like a Radeon 9600 Pro, or replacing my hard drive with a nice serial ATA model. Oh yeah... not a bad way of spending three grand if you ask me.