To be specific, there's no multiplayer in the Xbox 360 and PlayStation 3 versions, because there is on the Wii, PSP, and DS. As far as specific reasons are concerned, we don't really like to get into the reasons why we don't do things because I don't think there's really a satisfactory answer that people would really be happy with. So, there isn't multiplayer and that's kind of how it is...
hmm...
http://talkingaboutgames.com/content/view/1097/1/