So despite some initial confusion about whether the Wii U was an accessory or a console successor to the Wii, I now understand that it is, in fact, a new console.
During its initial presentation, Nintendo lavished about the fact that the Wii U would be fully backwards compatible, at least with the Wii.
I have also heard that it will use similar disc-based technology as its predecessor, and I was wondering if that applied to the Gamecube mini-discs as well (which the Wii was able to play).