I saw this video over on Tech Puddle, but it looks like their server is down as I've not been able to access so I'll link the video from here too. I thought it was pretty interesting, ignoring the fact you're trying to compare graphics quality on a YouTube video.
What do you think? The PlayStation 3 version looks really washed out and doesn't have the details of the Xbox 360 version, and according to the reviews it has a lower frame rate too. The Wii version looked a lot better than I was expecting, but still lagging behind both.