The pretty damn amazing Mario Kart 7 ad currently showing looks pretty damn amazing. So amazing that it'd be easy to assume the entire thing, actors aside, was computer generated. But it's not!
As you can see here in these short making-of clips, the ad team built real karts for the action. And didn't just build them, they put 'em to work on serious stunts, like Mario here flying off a ramp.
Behind The Scenes Of Mario Kart 7 's Commercial [GameSet Watch]