+1 for Jabber.
Someone joined our spanking new IRC channel last night (#ohloh on irc.freenode.net) and alerted me to jabber chat groups. They offer similar functionality to IRC: you can reserve a 'well-known group name' (for example: ohloh@conference.jabber.org) and offers basic moderator controls.
The benefit, to me at least, is that this integrates much better with IM clients. Not that I mind IRC that much, but I've got to admit that I don't enjoy the esoteric commands and bots very much.
In any case, we'll officially stick with IRC for now - it's way more popular. Secretly, I'll keep rooting for jabber chat groups to take off.
+1 for IRC. I even use Bitlbee to map my IM connections to my IRC client. In general I have the feeling that IRC is more etsablished and accepted in the OS world. Just my .02.
There's a summer of code project on the XSF idea list to make irc channels transparently bridgeable to jabber rooms. Seems like it would solve this nicely :)
(there are existing solutions, as Jason mentioned, but my understanding is that they're a little clunky. I could very well be wrong though, worth checking out!)
the project inkscape using bridge jirc, view:
http://outflux.net/software/pkgs/jirc-bridge/
http://outflux.net/blog/archives/2006/07/30/jabber-to-irc-bridge/
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