Chat rooms simply echo input out to everyone that is connected. There's no record. The equivalent to an FR thread is if everyone was constantly reloading their browser and displaying everything that had been written since the post was started.
However, I think that a chat room would be a good idea. There are open source implementations out there, and a simple Java client could be downloaded into your browser. It wouldn't work for some tablets and phones, but it would be available to almost everyone else.
Well, I’d like the chat room but I’d want it to work on an iPad!