Well, so the first is the biggest innovation to mention, namely the gamepad, of which I was a little scared, because it is almost as large as the console itself and so I had not imagined it, because there on the Werbund and Figure but looked much smaller. Something I can not find the size, however, because the gamepad is still well in hand. It is also emphasized that you can even without the Wii have the gamepad u on your TV, for surfing just like a tablet may be used. The compounds in the games between gamepad and TV are quite reasonable and devised clever by Nintendo, so the game does not suffer from the two monitors;) Alternatively also be played on the gamepad while the TV for other things is used. Yes, the game pad can even be used as a remote control for many types of televisions.
It should also be mentioned that when gamepad and old controllers of Wii are used, you can now play in some games with up to five players.
As an alternative to the "old" Motion Plus controller is now the Wii U controller per (not tested), the Motion Plus controller can, however, use them for every new game and for some even a prerequisite (would have been a pity for them, because they make quite a bit of fun out I think).
Who does not want to lose his old stored Miis, I can recommend the Miis simply from the Wii or the Nintendo 3DS to transfer u to the Wii, this is very simple.
Another innovation is the network Miiverse, which is intended to maintain a social network and also the Wii U Chat is new.
Especially I welcome, of course, that you can play all the old games from the Wii on the Wii U, these switches can easily return to the old Wii Menu, the Wii U so to speak Wii and Wii U is in !!
The problem of Wii u my opinion is not that it's just a bad console (because that it is not far!), And therefore the sale is going badly, but that simply many of the most popular games (the Mario series) still not at all on the market and just a few people and buy the Wii to their will but are keen on the new games, so I hope that Nintendo will this bring out soon !!
Overall I can say that I am completely satisfied with the Wii U and now just still missing the right software for this console :-)