Point your irc client to the server irc.freenode.net and join
channels #darcs (for general discussion) and #darcs-theory (for
focused patch theory discussion)

You can find searchable logs of #darcs-theory at

-  `http://irclog.perlgeek.de/darcs <http://irclog.perlgeek.de/darcs>`_
-  `http://www.ms.mff.cuni.cz/~lden8181/public\_darcs\_IRC\_logs/ <http://www.ms.mff.cuni.cz/~lden8181/public_darcs_IRC_logs/>`_
   (prior to 2008-09-01)
-  `http://irclog.perlgeek.de/darcs-theory/ <http://irclog.perlgeek.de/darcs-theory/>`_