While I glaze at the idea of an integrated communication network (about a specific topic, that is) comprising a NNTP interface, a mailing list, a web-based forum, and possibly even instant-messaging and chats (in such a way that conversations may be digested and exported to the other media for further discussion), all with full interoperability, I understand that such a beast would require an infrastructure that cannot be an afterthought and goes far beyond the current capabilities of PM.

All in all I strongly doubt that that would be a feature that could be easily added.