I had all three consoles.
I really liked the xbox 360 due to it's exclusive games like gears,halo,alan wake,mass effect etc. Most of my friends play on xbox live too so that was a big factor but it rrod and my warranty was out so I probably will replace it eventually with a 360 slim. Oh I regret not finishing alan wake and not being able to play halo reach and fable 3 which both looked awesome.
The ps3 is my main console right now and I really like the exclusives on here too but it just seems a bit more diverse then the 360 list. So thats a good thing. I enjoy uncharted 2, demon souls,killzone and some others. PSN is good too but I prefer xbox live more for some reason, more features I guess. But PSN is also free so thats a evens it out. I'm also looking forward to exclusives like gt5,killzone 3, and infamous 2 are some.
Lastly the wii is my least favorite console out of all 3. I just don't enjoy it that much at all. I guess the whole motion controll thing got old quickly for me and with lots of shovelware instead of games I wanted when I first bought it. So eventually my interest in the Wii just declined and now it just collecting dust,not to mention the lack of third party games that interest me. But that might change with the last story though wich looks good.But as of now it is my least favorite of the three.
So for overall I would have to say ps3.