Now, I had a rather mixed response to this. The pragmatist in me thought, "Oh, cool; they were able to take more comprehensive notes on the event with this neat piece of collaborative software." The idealist in me thought, "Wait, this is bad; it increases reliance on software that is not only closed, but is developed by people who are openly hostile to users' freedom to interoperate." Finally, the pragmatist in me came around, "Oh crap, if I were there, I wouldn't have been able to take part in this. No good!"
So, with the help of the excellent Obby protocol, the dynamic power of Emacs Lisp, and some spare hacking time in the past three days, I've come up with Ebby, a library that allows Emacs to collaboratively edit documents in a synchronized way. It doesn't have a shiny icon, but I hope you give it a shot.
Note that Ebby only runs as a client; you'll have to get Gobby to run as a server to connect to. Ebby connects to Gobby version 0.3, which seems to be the latest stable version at the time of this writing. If you can't install Gobby, (or just don't feel like it) you can try connecting to my server at technomancy.us, but there's no guarantee that it will be running at all times.
So please try it out and add your comments to the wiki. Don't be shy about filing tickets for any problems or patches you may have.
Update: critical bug fixed; please grab a fresh copy!
Update: Ebby has not been updated for the changes in more recent versions of Obby, but Rudel has, so try that instead.