I'd say it depends on what you're friends play. You'll probably want to play online with them, and that would be the biggest deciding factor. If all your friends have one console, you should probably get the same one. Otherwise, if it is split 50/50 then read the rest of this post

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Most good multiplayer games which are worth playing are on both consoles (street fighter IV, CoD 4/5/6[when it gets released]). As for console exclusive games, I think all the PS3 ones are crap

. Metal gear solid 4 is basically a cutscene. Kill zone 2 just has pretty graphics, everything else is completely mediocre. Some
crazy people like the games which I hate, but I think it is just because they release them on the console they own

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In terms of controllers, the 360 one is more ergonomic, but the D-Pad is completely useless. The PS3 controller has a damn awesome D-Pad

. The thing is, unless you plan to play Street Fighter IV (or any other 2d fighting game), you don't need the D-Pad.
Asking such a question on the internet is pointless, people will just recommend what they bought because they will try to justify to them selves that they made the right choice

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Like this:
Get the PS3! It can play blu-rays!@#!@ In the long run it is cheaper because you don't pay to play online(for the 360 you have to pay for "xbox live" to play multilayer games). It has an awesome D-Pad!! woo!!
PS: if you haven't figured it out, I own a ps3(only use it to play street fighter 4 and watch blu-rays + stream movies from my pc to the tv )