It was quite clearly stated that Sonic Generations is not coming to the Wii U. That’s what made this statement from Mike Hayes of SEGA so curious:

We’re doing high definition Sonics, we’re doing obviously Aliens: Colonial Marines, so you can bring them across, and that’s relatively low cost, which is good news.

…but perhaps he just picked a bad example when discussing the benefit of bringing their games to the Wii U. Still, if there’s money to be made Sonic will hit the system.