I have a Mercurial repository for a personal project, and I have been storing the master repository in my Dropbox for a few weeks now (something along this line; and I under
I've been using Dropbox with Hg too without experiencing a problem until now. Too late I realized hg doesn't report corruption during routine checkins, only when you try to use the repo for real (the worst of all situations, since you don't know something's broken until you really need it).
Its not clear whether if the corruption is spontaneous or caused by accessing the repository with Mac, Windows and Linux clients (I use all three at different times). But I've seen at least one case of corruption happening when only the Mac was active so it could well be Dropbox itself.
If you do decide to live dangerously, run "hg verify" (or "git verify" regularly to turn up any dirt.