For comparison sake, I learned to ride a unicycle (level 2 ish) with about 8hrs of concerted practice spread over a couple weeks. A lot of the problems you encounter in the video (difficulty mounting, speed control, not falling on your face) are exactly the challenges with learning to ride a real unicycle.

I highly recommend trying it out sometime - it's a surprising amount of fun once you get the hang of it.

EDIT: Unicycling levels - I'm probably about a level 3 (on a good day). Neat sport with interesting progression - perfect for programmers that like to level up and get good at things (and stay active!):

http://www.unicyclist.org/cont/levels.cfm