I'm actually kind of surprised, that the front-page article "comments" feature, isn't actually implemented in terms of a forum (well, it probably is). So why not expose that forum among the "regular" forums as well? I find it annoying to read and reply to the article comment threads, because I have to disable my local HTTP proxy and reload hte page in order to get the pop-up with the discussion. I hate pop-ups.
(So therefore, exposing those discussion threads as a forum would be useful, IMHO.)