Jonathan Hartlet, "made of meat," wrote up "A Guide to GIT using spatial analogies," which tries to explain git's branching mechanism in the most absurdly complex way possible. It might be humor, but maybe not.
One of the things that tripped me up as a novice user was the way Git handles branches. Unlike more primitive version control systems, git repositories are not linear, they already support branching, and are thus best visualised as trees in their own right. Branches thus become trees of trees. To visualise this, it’s simplest to think of the state of your repository as a point in a high-dimensional ‘code-space’, in which branches are represented as n-dimensional membranes, mapping the spatial loci of successive commits onto the projected manifold of each cloned repository.
Honestly, I thought I had a decent grasp of git, but after reading this, I'm pretty sure I'm running right back to SVN. In fact, now I'm afraid of SVN too - I might go back to CVS. Or RCS. Or tar.
OTOH, if you were trying to explain git. What would be the things you think people don't get about it? How would you explain those things?