Soundwave on 10 April 2013
The Wii had more exclusives like Red Steel 2, The Conduit, Resident Evil Chronciles, Little King Story, No More Heroes, Grand Slam Tennis, etc.
The Wii U has a few more multiplats of some more mainstream franchises like Call of Duty and Batman and Assassin's Creed.
Depends on which you prefer. If you have a PS3/360 already, then its probably worse for 3rd party suport. If you don't have a PS3/360 then its better than the Wii.
