Efficient way to backup maildirs from post-sync hook?

[seanh]

On Sun, Mar 06, 2011 at 08:18:21PM +0100, Christoph H?ger wrote:
> what about using rsync --delete and git as a backend? Git seems to
> be reasonable fast and would give you the meta-data (dates, diffs,
> etc).

I don't understand. How would I combine rsync and git? Why wouldn't I
just use git directly?