I have all 3 consoles this generation, my Wii I'm not even sure were it is, think it's in the loft somewere, I use the Ps3 as a blu ray player and web browsing in bed.
My 360 I use for gaming for the simple reason the controller is best suited to most games, especially action games were one analog stick controls the camera, and the other charaector you are in a particular game.
If your only interested in gaming, get a 360