Expanding on the Conference Chat idea, I think it would be great if voice would be included. This was one of the best features of skype. Ofcourse, voice chat is optional. The topic is moderated by the topic creator. E.g. You create a topic and wait till people join. Each person that joins is a 'spectator' but if they want to particpate (talking instead only reading/listening) they can ask you to move them up as an 'active participant'.