IRC is an excellent public forum -- both for helping users and for getting to know other committers. We have official group status on Freenode. You can connect to Freenode by pointing your IRC client at irc.freenode.net. We maintain the following channels:
#eclipse - questions from plug-in developers and users #eclipse-dev - Eclipse committer discussion and socializing #eclipse-commits - lists all commits as they come in (See CIA)
A log of the the traffic on #eclipse is available on the web.
There is a second Eclipse IRC FAQ available on-line.
If you are a committer, then you can get yourself a developer cloak. A developer cloak identifies you as a committer on the Eclipse project, gives you some privileges on the channel and masks your hostname. If you would like a developer cloak, please contact desudation or Kurrelgyre on IRC.