I'll try and answer some questions that some may have about the Wii U.
Firstly, it's backwards compatible and if you want to do so, you can import saves and online purchases from the Wii onto the Wii U. The eShop has optimised a few NES/SNES/GBA/DS games to play on the gamepad so you don't need the tv to play these games. Wiimotes and nunchuks still work on the Wii U, although most games (to me, anyway) don't require them. That said, it couldn't hurt to have one or two of them.
The GamePad is pretty nifty, it's basically a tablet I suppose. Has touchscreen, microphone and accelerometer for motion controls. It's surprisingly light and comfortable for it's size, although it's battery life isn't amazing (I think it's four hours). If you can, grab a Wii U Pro Controller which normally run for $50-60 and have a battery life of 80 hours once charged. Also, these controllers can be used not only for Wii U games (not Wii though) and games you can buy on the eShop. I can't rate them enough, I held off buying one for way too long.
Games wise Mario Kart 8 has been the first real big seller, but there's a still a few games worth looking at too.
Super Mario 3D World is fantastic. If you like Mario games, get this.
Pikmin 3 is a quirky, beautiful game. Different but definitely worth a look at.
Legend of Zelda: The Wind Waker is just ******* amazing. Even if you haven't played a Zelda game before, look at this.
Those three are my absolute favourites that have come out so far. But there is a promotion that if you buy Mario Kart 8 before end of July (I think) you also get to download
one of these ten games for free.
There are two different types of Wii U available,
basic (white) and
premium (black). Basically the premium comes with stands, a sensor bar (necessary if you want to use Wiimotes), larger internal memory (32gb to 8gb, although external is an option too) and Nintendoland game. I haven't looked at prices for a while, but I'm assuming there would be some decent deals getting about now it's end of financial year.