A request for v2 -- I'd like more on topic branches, and good git hygiene. I usually send people to your book, and in fact, I learned my first git from it.
In the end, though, it encourages using git as a sort of backup-and-restore system, which is not the best and highest use of git.
The best and highest use of git is going to involve rebasing, collecting up and properly naming your commits, and making CERTAIN that one commit does one atomic thing to your codebase.
This just wasn't that obvious to me from git magic, but I think in the end it's the best part of git as a whole. Once I get people to stop using git reset --hard, my next training task is usually what I just described.
Anyway, if you really like this, you should consider getting a physical copy: http://www.amazon.com/Git-Magic-Ben-Lynn/dp/1451523343/