Hey Steve, I just checked it out, pretty slick! I enjoyed the write up as well.
I wonder if their is some way you could store the irc session in the django session (or wherever) so that if you navigate away from
http://mezzanine.jupo.org/irc/ (for example you go to the archive) and then come back you are still logged into irc. I haven't looked through the code and have no experience with IRC development so I have no idea if that is feasible.
I think the IRC archive is a great contribution to the community.
Also, for anyone looking for it here is the github project:
https://github.com/stephenmcd/gnotty (I think you accidentally linked to the Mezzanine project Steve).