A portion of an NWR interview with Sonic Team's Takashi Iizuka...

NWR: The demos on the floor are all single player. Can you discuss the co-op and versus multiplayer?

TI: We'll have different multiplayer modes on both Wii U and 3DS. On the Wii U, there's booth cooperative and versus multiplayer. In cooperative play, Sonic will be using the Wii U GamePad and someone can be supporting Sonic in co-op with the Wii Remote. In versus mode, one player will be playing on the TV screen and the other player will be racing using the GamePad so you don't have to have split screen. You both have your own screen and can race each other. The Wii U multiplayer is not on the Internet. It's basically everyone sitting on the same couch. The 3DS for the first time we're having 4-player versus racing over Wi-Fi and the Internet.

NWR: One more question here. Sonic was very popular in Smash Bros. for Wii. Is there any possibility of him making a return appearance in the next Smash Bros.?

TI: All we can say is that we also think it would be awesome if he was in the next Smash Bros. So yea, but that's more of a question for Nintendo than us.