I'm a PS3 kinda guy. I have a wii too, and that gets broken out more when people are over, but I probably spend more time on the PS3. And come on now, this whole "360 has better games than PS3" thing is kinda dated. There are VERY few titles on either side that come out exclusive to one system these days, the exception being in house Sony and Microsoft games. The recent big titles like COD4, GTA IV, etc. all come out for both. And yes, MGS4 looks like it'll be cool.
The nail in the coffin though, is that xbox 360's literally kill babies.
Lawsuit Claims Microsoft Xbox Sparked Fire That Killed Baby -- Xbox -- InformationWeek
and let's not forget the famous
Red Ring of Death