On one hand I think this is an innovative presentation, and I enjoyed the creativity. Also I like fonts.
On the other hand, (and this is a critique of scrolling/parallax navigation in general), as a user I always feel like I'm doing this wrong. It feels like I'm a cameraman with one of those old-timey hand-cranked movie cameras from the Charlie Chaplin days where the skill was in keeping the shutter speed constant but I'm doing it wrong and everybody is walking around at a weird speed.
The ability to reverse the animation by scrolling up is novel, and maybe going at my own pace is the idea. But personally I would rather click next and let the transition happen normally. Maybe Powerpoint has made me lazy.