While the Wii version will have an awesome multiplayer duel mode, the PS3 and Xbox 360 versions won't be getting any multiplayer component.
LucasArts' official statement on the matter:
"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..."
You aren't putting multiplayer on the two consoles with the best online multiplayer services because you're putting multiplayer on 3 platforms that are at the bottom of the multiplayer barrel?
You just got downgraded to rental, Force Unleashed.