It's already Nintendo Kart. They only use the Mario Kart name to sell more copies. I've been bitching about how Mario Kart was suppose to be a race circuit in the Mushroom Kingdom ONLY for years now, and no one else seems to care. Maybe part of that is because I am old enough to remember playing the first game (still the best one imo) and that's how it use to be.
But yeah, it hasn't been "Mario" Kart for years now.