It's really easy to pick up your 360, or PS3 controller, play a game, and then say "damn, this is missing something." It's not that easy, to add what is missing. You can't bend a games framework when you're working with a console, or at least not that I know of.
When I look at the power of a good PC, I seem to realize more and more, that a decent tower can out-do bother the 360 and the PS3. There is the price issue, and graphically, I don't care too much, but what's getting into my head are the mods.
When you can literally, make a game your own, you can have some serious fun. Let's take Oblivion for example. I played the hell out of it. I completely murdered my disk, and it became just as much a part of my 360 as the hard drive was. But then what. It's done, what to do?
Had I had the PC version, I could mod, expand, and enjoy, all at will. And if mods weren't avaliable, I could make them. I could put my dreams, into a game. Now that's deep.
I'm not jumping ship from console. I'm just adding another deck.