The 80's and 90's are still alive and well on irc.freenode.net.
I am idle in various channels in IRC all day, and just yesterday I was wondering why there was no channel for IntelliJ Community Ed. and Open API.
There are at least 10 channels for Eclipse. Why not one for IntelliJ?
I don't know that anything will ever replace IRC for open source projects.
An official channel would be nice, but if there was interest we could make an unofficial one.