As a Video Game Specialist, I say they are both very much alike, it really depends on the develpoers and what console they created the game to best on, when it comes down to hardware the graphics are better on the xbox 360 as well as detail, draw distance and anti-aliasing, especially on Fallout 3. But when it comes to gamma, brightness and character polygons the PS3 will take the cake most of the time. Even though I don't like PC gaming, it is true that games from this year on will play better on a real PC gaming machine. This comes from a game enthusiast and a fan of ALL consoles. It comes down to what you want anyways.
I own both systems and Assassins Creed on both, it was free with both lol. It is very easy for a real gamer to see the diffrence, and here is what I see here and what I see when I play both versions: Detail = 360 - Shading = 360 = Draw Distance = 360 - Fps = PS3 - Character Detail = 360 - Controls = 360 - Anti Aliasing = 360. But remeber this is just for Assassins Creed game, and the game is not made for the two consoles, it just depends on what the developers try harder for and the hardware for the game itself.
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