Thanks. Hadn't heard that Rayman Origins PS3 audio was "gimped", so I Googled it. Someone on GameFAQs claimed the 360 only has stereo tracks, too. So far haven't read a post from someone who said they had both and compared the actual output (vs. what's on the box).
It's actually not gimped, but I heard that the 360 version outputs Dolby Digital 5.1 surround, while the PS3 instead outputs dolby 7.1 pcm. So if you have a receiver that accepts that format of surround, the PS3 has better audio. It's just that most of us only have dolby digital 5.1 setups and so the ps3 version defaults down to stereo if our settings aren't 7.1, which makes people think it is inferior. Not sure why they didn't offer the more common 5.1 on ps3. If you just use your tv speakers, it doesn't matter which you get.
Graphically, I personally thought the 360 picture was more vibrant and cartoony, while the ps3 was a little more earthtone and darker. So the 360 version seemed more appropriate for this style of game.