I've been a PC gamer for over 20years, and a console gamer for just as long.
We all know PC games have been years ahead of console games forever, and the graphics capabilities will always be better. I too enjoy using mouse and keyboard when playing competitive shooters online like Battlefield 3. But to say that K/M is far superior controls in general is ridiculous.
Having a controller in your hands with all buttons and controls mapped intuitively is far better in MOST games. I've even tried BF3 with my controller in 64player matches and still done well, especially the vehicle, tank, and jet controls are SO much better with 360 controller. And yes even tho mouse is faster, it isn't by that much once you're good. Back in the Halo 2 days I'd have my sensitivity at 9/10 and got to where I was just as fast and accurate with kills as I was on Unreal 2004. Point is tho, in single player games, where you don't need that extra split second of aiming to kill the AI opponents, a controller trumps K/M most of the time, in comfort, intuitive mapping, interaction(rumble), etc. I'm at the point now with my home pc hooked to my 50" TV that I don't buy any games that don't support controllers(I still play others at my office pc lol)
I used to be a K/M elitist, saying "Oh you just haven't tried K/M so you're stupid cuz it roxxorz" but in all honest reality, you "elitists" are the ones that probably haven't even tried using a controller and seen how much easier, more convenient and fun it is to sit back and relax with one. Not to mention having full analog for games like Assassins Creed and racing games like Dirt 3, or even getting lost in Skyrim. So much better with a 360 controller. Period. Try it