Yes you read that headline right. I was using IRC in the 90s and it is back in my life in 2011. Drupal maintains a number of channels on http://irc.freenode.net that are used for support and discussion.
I joined IRC as a way to assist others who are just beginning their Drupal adventure. These days I do not need to do as much research. If I encounter problems I just look at the code. Things have become much easier than it was in the early days.
Want to join Drupal's IRC community? Just read the rules.
If you're on freenode I am registered as user weal. Running a /whois you'll see I connect from montreal.weal.ca.