Basically, the most important thing you need to look at when buying games for PC is the graphics card. It's usually no problem that the other parts of your PC are a bit below the requirements if your graphics card can keep up.

Having just tried this game with a Geforce 8800 GT, i can say that it's no problem running it at high graphical details, 2x AA and high textures, which puts the graphical quality on par with, or greater, than the consoles.