I think you're not considering the possibility that this chat is specifically for the Stack Overflow community, not for people who have no interest whatsoever in Stack Overflow. Your complaint is like saying, "HN wants me to register to comment? Screw that noise, I'll just hop on IRC and comment there!" You're perfectly welcome to do that — but you still have to register to comment on HN. Different communities have different and often somewhat arbitrary standards.

It seems pretty good as far as things like this go, and I'm sure it'll do ok, but a big part of anything like this is network effects: people go where other people are.

My guess is that SO is currently big enough to attract viable communities for several of these "channels", but that many others will end up as ghost towns, and that, overall, IRC will continue to be 'bigger' for real time chat. It's probably a big enough space that this can be successful in its own right, even if it's not huge, although I think I will tend to prefer IRC.

Also, signing up for HN is way faster than having to ask/answer a question.

Not to be rude, but StackOverflow is a Q&A site. Why would you not just ask the question you had there instead of trying to answer questions to make it to the chat rooms?

You'd probably get enough reputation from that question to be able to ask your next one on the chat rooms if you wished.

We were talking about the chat, not SO as a Q&A site, which is something it does quite well - much better than IRC for some things.

I went on IRC countless time to get answers, and depending on what, when and where you ask questions, the answer ratio is really low. Think about it, some pretty good people are camping on IRC, but sometime they are going to sleep. SO is asynchronous by nature and there is a real motivation for people to formulate good answers and good questions. SO is the resume of the future!