I just read the darcs manual, cover to cover (it's not that long). I've got a couple of repositories set up the way I like, and it seems fine.
One thing I would have liked a more thorough description of in the manual is the subject of branches. The paragraph about that is very thin. What is the best/usual approach to creating branches for release-versions and stuff like that?
Another thing I would like to have is to have an email generated on each checkin (push/send, I guess) with the diff of what has been put into the repository. (Only for some repositories - the ones I use in a centralized fashion (the ones I'd have a webinterface for as well), of course). After reading the manual I'm not sure how to do this (or where to look) or if it is possible at all.
Oh, and tiny things I don't know whether are "problems" or just user error: owner/group/permissions and symlink-handling, how?
And finally this slight annoyance:
$ darcs changes Mon Aug 15 02:35:30 CEST 2005 Adam Sj\f8gren
* Initial import. $
Update: The solution is in the manual - just set DARCS_DONT_ESCAPE_ISPRINT=1 ...