I like the size of the Wii-U if I compare it to the PS3, negative thing for me is the noise of the BD (..) drive and the fact the BD (..) drive can't read DVD and BD. Battery life of the GamePad is also not that good.
Games library is a bit to early to talk about but the fact some big games don't come to the Wii-U (like Far Cry 3 and Crysis 3) is vey disappointing for me.
So I see the Wii-U more as an add on for my PS3 as an replacement for my PS3.
Sony just lost the PS3's chastity belt keys, secret fun spots are open to explore ...