What do you think of bzr (aka bazaar-ng)? I say, get prepared now, and launch in sync with bzr 2.0.

Uh oh. This could be the start of a very long thread. One idea might be to take a look at using Tailor (http://www.darcs.net/DarcsWiki/Tailor) to try out or offer different repositories -- its seems to work well for syncing between cvs and subversion and I've seen projects that just off-load from CVS to mercurial for development. In any case you can use it to see what the code-base might look like in a different system. -Curtis