1 - There is a new console called Wii-u:
2 - There is a new controller:
3 - Wii-u console is able to do graphics that look way better than anything I've seen in X360 or PS3, at least from what I've seen in the bird&pond video, even more if it's being done in 1080p
4 - Wii-u uses Wiimotes, nunchucks, Wii balance boards, etc
5 - Backwards-compatibility with Wii titles.
6 - Four-player-per-console limit has been raised:
In a post-presentation demo on nintendo site I saw examples of a 3D game being rendered full on a HDTV with 4-player split-screen while a 5th player joined the game with the new controller, and the new controller had 3D game rendering too.