That video, or at least parts of it I've seen on TV before. One of those "craziest videos" shows or something like that. They did something like that on Jackass once also, except the guy doing it ended up wiping out big time around a corner.
I remember going down a moderately steep hill on rollerblades once. I hit maybe 20mph and was about to piss my pants. I can't imagine going 60+ on 2" wheels.