I am very familiar with forums online and while I have no idea what the total user count is on this board, I doubt the chat would be active enough.

Another idea is to start a live (or prerecorded) live chat like sports talk stations do on the radio. A show can have a couple host, there is a call line so people can ask question, and this can be done for free. This would possibly be interesting to do once a week or once a month. The shows are saved once they are completed, so we can go back to them, and all of this is free. http://www.blogtalkradio.com/

It would also promote the site.

2 Cents