Just from watching that clip, he seems a lot faster than most other guys of his extreme size (Think Yao, Rik Smits, etc.). It sounds silly, but that extra few inches over seven feet always made guys seem like statues. He seems like he's got the ability to move without the ball and even has some shooting touch.
Obviously, he's being guarded by guys who're a foot shorter than he is who, all things considered, probably have no business playing basketball, so it's hard to gauge how truly dominant he is (or can be, for that matter). He's the kind of guy who would definitely benefit from two or three years of college ball to hone his skills and bulk up a little bit. I mean, if this guy eclipses 300 pounds, he'd be impossible to move on the low block.