In what I now recognize as David’s style, the dancing starts slow and simple. Just when you’re about to dismiss him as a dork, things get "liquid ":http://en.wikipedia.org/wiki/Liquiding, locking, popping. Frankly I didn’t know the body could move that way. And no, it is not computer animation.
There are tons of videos available of the man but perhaps the most famous is his participation in Kolla2001 (David is the 3rd dancer to appear)
And just to cast away any thoughts that this requires digital trickery here 2 extremely simple tutorials (simple enough even for me to follow):