Up till this past 6 months (less, actually) I played mostly PC games... there are a few things the PC is better suited for.
1) FPS (First Person Shooter) - the Mouse-Keyboard combo is much cleaner (once you learn it) than any game controller. I'm playing Halo on my XBox now, and while it's very playable, it's only so because the game was designed with some "play" in the aiming.
2) RTS (Real Time Strategy) - RTS games tend to be mouse driven. The only RTS I've played on a console has been the N64 version of Command and Conquer which played fine, but it was easier on my PC with the mouse (and # keys for grouping troups).
3) Tycoon/Simulation games - i.e. Rollercoaster Tycoon, Zoo Tycoon, The Sims, Sim Earth, etc. While some of these titles appear (and will continue to appear) on consoles, they all just about demand a PC, both for the mouse-interface as well as trading/customizing parks/cities/rides, etc.
4) Mod-ability - Take just about any game and you'll find some Mods for it (some more than others, Half-Life, Theif series, Unreal). It's just not doable on consoles. Sure, XBox is supposed to support downloadable content with Live, but that doesn't do anything for all the fans who make their own maps/missions.
Frankly I goto EB to get most of my software (that and Walmart). With EB selling used PC software (and lots of older cheaps stuff) I was able to build a large collection of good software, most of which I paid no more than $10-15 for (each)... many under $5! (Theif Gold for $2.99
).
So, PCs not dead.. however
In fact I got the XBox for the same reason I got a N64. Too many problems meeting system requirements, tweaking, etc. I'd have to throw out my whole system and get a new one to play anything comming out now.
Down the road I'll replace the PC and give a new round of FPS and RTS games a run.. till then it's more arcade style stuff for me (not that it's all that bad).... now if they'd just score some Square stuff we'd be in business
PHIL