This is a feature. Most of the people on an IRC channel are lurkers. And the channels are very quiet so that people can hear you when you do speak. Believe me, I wish they were quieter, because even as they are they tend to be too distracting for me to lurk there while working.
It does seem creepy. Our company's salespeople laugh at the programmers because we really love to gather in one physical room, then sit silently next to each other typing on laptops and communicating largely via Jabber chat and IRC, even though we are two feet away from each other. If you've never tried to concentrate on programming this seems like alien behavior, but it actually makes a lot of sense, for the same reason that it makes sense for all the Drupal devs to sit in one IRC channel but almost never speak.
If you crave more chat, join more channels in parallel.
I guess I don't actually find the 300-lurkers-who-never-talk channels much of a feature. Much prefer the ones with 15-30 or so semi-active users. There can still be large periods of not chatting, but you know who's there, and there's a decent chance that when someone does say something, it's relevant to you. There's a difference between sitting in a room of programmers quietly, and sitting in an auditorium of programmers!
Ive done this, it is amazingly productive. We had jabber server at one place, and all 10 devs were in the same room physically, as well as the chats: #dev #dev_pvt #dev_funny #dev_offtopic #bugs as well as having a dozen side conversations, and talking out loud in the room. Never too much time blocking on conversations, and easily ignorable when working on something deep, but since physical presence is happening, anything super important can trigger an "out loud" interrupt.
It does seem creepy. Our company's salespeople laugh at the programmers because we really love to gather in one physical room, then sit silently next to each other typing on laptops and communicating largely via Jabber chat and IRC, even though we are two feet away from each other. If you've never tried to concentrate on programming this seems like alien behavior, but it actually makes a lot of sense, for the same reason that it makes sense for all the Drupal devs to sit in one IRC channel but almost never speak.
If you crave more chat, join more channels in parallel.