Sega has said that Wii U "is coming out next spring/summer."
In an interview with GameSpot, Sega's executive vice president of marketing Alan Pritchard was explaining why Sonic Generations won't be released for Wii U when he said:-
"The timing just doesn't work. Generations releases this November, and the Wii U is coming out next spring/summer.
"To bring out Generations on a platform six or eight months after we release PS3, 360, and 3DS probably won't be the best strategy," he said.
Of course Nintendo hasn't confirmed when Wii U will be released and this Spring/Summer date may well be wrong.
All we know for sure is that Wii U will be released in 2012.
[ Source: GameSpot ]