So I own both an XBox 360 and a PC. The PC has a GeForce 295GTX, Intel 980X, Intel 160GB SSD, and 12GB corsair dominator ram. Even with this configuration,
PC GAMES AREN'T ANY MORE FUN
Although I do appreciate the increased frame rates, textures, and random cool effects, it's still the same butt-kiss 3D that I've been seeing for the past 5 years, just more detailed.
The only thing game changing nowadays are games with destructible environments. Battlefield: Bad Company 2 is the most recent example. However that's still not enough. People's facial expressions and skin still looks plastic and fake. Too many hard lines everywhere. Explosions of something that generates millions of shrapnel particles still take too much CPU. I can still see the effects of draw distance, etc.
Given this, and the need to develop a game, then PCs should take second seat to consoles, and if and only if there's enough of a justified budget should a port be written. Maybe in 5 years things will be different, but by then consoles will have had a hardware refresh, and PCs will be back at square 0 trying to compete.