Review scores are mostly inconsistent across platforms. Let me give you an example sometimes a c64 version of a game scored higher than the Amiga version, while in fact the Amiga version offered better graphics and stereo sound and music while offering identical gameplay. But why did the c64 version score higher then? Because the reviewers were amazed by how far the c64 could be pushed, while on the Amiga they had already seen much better.
I think if many of the Nintendo Wii games would have been released unenhanced for the PS3, they would have scored far lower. That's of course biased, as it's the same game, but that's how it is. Else it would be impossible for Nintendo Wii games to receive near perfect scores for graphics and audio if directly measured up against the competition.
