The link below shows off the new unannounced but heavily rumored Xbox 360 controller in action.  The demos show the use of the Darwin controller with Tiger Woods '09, Lego Star Wars and new Harry Potter game.  The Darwin controller is split in to two pieces and they demonstrate how they played co-op in star wars.  I think we will be seeing a lot more of this in the coming weeks and don't be surprised is some big games like Fable 2 or Gears of War 2 support this controller.

Source:
techradar.com - xbox-motion-controller-video-demos-inside