Yup: IRC is still very active. Maybe not the mid-to-late nineties craziness, but certainly still around.
I spend most of my time these days on private networks, but I'm also in #startups on Freenode. Lots of good conversation in there, and a lot of HN regulars.
Still big. Not quite as ubiquitous as it once was. I'd say there are far more people in support channels, and less people in purely social channels than was once the case.
Edit: Internet Relay Chat chat. Sorry. Couldn't help myself.
Even though it's still very much alive and kicking... I wonder what medium has taken over IRC's popularity and on what merits? At least it hasn't grown at all, despite how much general internet usage has grown during the past 10 years.
I spend most of my time these days on private networks, but I'm also in #startups on Freenode. Lots of good conversation in there, and a lot of HN regulars.
No better way to find out than to give it a shot!