I'd play you at COD5, but I can't get on CricSim to organise it at my dad's where my PS3 is >_< Yesterday is the first time I actually had some succcess as a sniper, and didn't just get massacred.
I've never played CoD5 online. My brother has played on it under my name heaps though so I suspect I have a good-ish ranking.
Why, because you can only afford a 360 and because you can't afford both you develop a disgustingly biased opinion and defend the console too death.
I have both in this house, but I don't own the 360... Played them both at home and work, and much prefer the PS3. It's like Snake said, it's cheap enough for some to aford, so they pretend that it's gun to themselves.
If you just play multiplatform games (like 99% of the people here do), obv XBOX360 is the best way to go. I'm a Sony fan, but even I can see that.