The following info comes from Mario Kart producer Hideki Konno...
On considering characters from other franchises for Mario Kart: “No, we’ve never seriously considered that.”
On Mario Kart heading to Wii U: “I can’t get into the specifics, but I do want to create a new and enjoyable Mario Kart that uses the unique functions of the Wii U. Anything beyond that I have to keep secret. Please bear with me for now!”
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