Although I think Mario kart will still be the king...
SourceThere was a rumor that SEGA All-Star Racing 2 was in development. This has been confirmed by Kotaku, but we don't know for what platforms. Still, the rumor stated it'd be on 3DS and Wii U, and I'm thinking that is a likely possibility.
My son loves sonic. If it's on the Wii U I wont be able to get him off it lol.