Hmmm,I think everyone overrates GTAIV,everything that was surreal and fun about the GTA games in the sixth generation has been replaced by a cold realistic gritty world in the new game.
I would say Playstation 3.
The Uncharted series is by far one of the best gaming series ever made.And the online gameplay for Uncharted 2 is superb.The loading times are shit.But the gameplay is there and that's what counts.
Little Big Planet's controls kinda put me off it to,but it's a nice game if your coming from Ninty background,just to ease you in to the HD world of gaming.There's nothing like it on 360 from what I've seen.
Next year see's the international release of Final Fantasy XIII which simply has to be purchased on a Playstation console,and FF Versus XIII is still an exclusive game to the PS3.
The Last Guardian looks to be one of the most cinematic and artistic games of this generation,as does Heavy Rain,you may want a PS3 to check them out.
On the other hand,the 360 has Natal next year.Which could be good for some people.My personal opinion is that motion controls like the Wiimote and shitaxis and all future planned ones be abolished,but people like them I guess.
The 360 has a bigger community online.Barely these days,that doesn't make it better in my opinion.I find the quality excellent on both consoles.
The Fable series looks to be one of only a few reasons I would suggest to you to get a 360.
But on the whole I think you'll find you'll get more out of a PS3 in the long run.
But aussie prices are daylight robbery :O $500 :O
Playstation gaming for 18 years this 2012 
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