Have you checked out the demo for Rayman Origins? Did you know it supports four player local co-op? I just signed in three other controllers and gave it a whirl, and it appears to be a worthy co-op platformer. I'll have to try again with three other people. A one-year-old and two pugs do not make good co-op partners. Check out this video and see all the different ways you can beat the game. You can expect our Co-Op Review soon.
Rayman Origins is out now on the Xbox 360, PlayStation 3, and Nintendo Wii. It supports four player local co-op.