The VCS software thing is really much less of an impediment now. Both hg and bzr (yes, I actually like bzr most of the three) export to git. I'd be using bzr for all my repos, if it didn't have a bug where "push" meant "push --force". I should look and see if they fixed it.
And in case you have missed it, there is work going on right now to add hg and bzr remote-helper support to git. In particular, if you look at the latest RC announcement[1] for git v1.8.1 we see
* A new remote-helper interface for Mercurial has been added to
contrib/remote-helpers.
and in the most recent "What's cooking"[2] (dev updates) we see
* fc/remote-bzr (2012-12-13) 10 commits
[snipped]
New remote helper for bzr (v3). With minor fixes, this may be ready
for 'next'.
A big hats off to Felipe Contreras[4] who has done a lot of work to get these updates rolled out. Not sure how many others have been involved, but thanks!
The latest RC is available from the usual places, for example [3].
