I just had a quick question about git - how backwards compatible are git repositories? Eg., I've created a repository using git 1.6.4 and the svn2git ruby script, but I want to put it on a machine that's running Debian Lenny, which has git 1.5.6.5. Would I still be able to interact with the repository properly?
It's extremely backward compatible in terms of the actual storage of information, which is all you're worried about in this case. I'm not a total expert, but I doubt that's changed since the first stable release.
The only compatibility problem I can think come up with is if the two versions of git are working on the exact same repo (not clones) and there are options/aliases set in the .git/config that work in the newer version but were not [fully] implemented in the older version... but even then you'd have to try pretty hard with versions this close. And again, this isn't anything to do with the actual information in the repo, just the commands you use to manage it. That's where the development of git is taking place.