They lack important parts.
The rumor mill on the intarwebs is grinding with the possibility that the Xbox 360 and PS3 versions of Force Unleashed will NOT have online multiplayer. Why? Because the Wii, DS and PSP versions do.
Wait, what?

According to PSextreme Adam Khan of LucasArts had this to say:

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...