I've been dealing a bit with advanced interface-design before, here & here. And in fact what Jeff Han is doing here is not really different from what Microsoft Surface can do. He just have a much better idea of what to use it for. In other words - this is so much more useful fx. looking at graphic visualizations of complex data, where the ability to both see the big picture and infinitely small details is important... rather than using it as an interactive sofa table... thank you microsoft for really making a difference.
Towards the end of the interview he says something really interesting about a possible 3D-version. It turns out the actual problem with this is that the human body has great difficulty doing very presize gestures when it doesn't have anything to push against. It's the problem of keeping your fingertip in an excact point in space, while taking a step to the side. Something that's very easy to do if you rest it against a wall.
So maybe even Jeff Hans design is a dead end too. Lot's of more videos of this on Youtube.