Erm, I think it's already been announced that the Wii can connect wirelessly with other Wii's making a wireless LAN party. Although I think you'll need two TV's, but who hasn't got at least 2 TV's nowadays? (In the whole house)?
Would this mean that 8 Wiimotes can be used in the same room without interferance on the channels? If so, does this mean a potential 4-player drumming battle could ensue? That would be mad!
