Two Additional Notes On Wii UOne, and I should have mentioned this last night, Wii U does have support for legacy Wiimotes. In some games, one person will use the new controller while the other players use Wiimotes. One new controller is the max the Wii U supports--in other words, if it's a multiplayer game, only one person can be playing with the new controller.
Confused? Yeah, so am I. And I think developers will be, too, although I certainly think it has potential for the single-player side of things.
Second note. Neil Sorens sent in an excellent point: I'm not sure that mobile/tablet games would work, because the controller apparently has no processing power of its own – the video is produced by the console and transmitted wirelessly to the controller screen.
An entirely excellent point.