Do a search for the "I'm in the chat room" thread, and if you're going in, add a post to the bottom of it to 'bump' it. That way, people on the forums will know there's likely to be someone in there. If you don't do that, then the chances of you randomly choosing to go in there at the same time as someone else must be practically nil.
I must admit that I haven't been in there for a while either. We really should start using it again. It used to be a right laugh :d