A lot of the times, chat rooms in forums tend to be really popular for the first few weeks then less and less people will use it. Subjects go off topic really easy and it becomes a drama fest. Its really hard to weed out the trolls and spammers. Also, if a it does get really popular, its gets really hard to keep up with the all the posts coming in as fast as people can type.
The only solutions I have found that works is to setup a chat schedule. Say, "Stingray Chat, Jan 28th 8pm pst." People interested in the topic will join in and the topic will stay the same. Its best if you have an experienced keeper there answering and moderating. The problem here is MFK has a world wide audience. A time that is best for all is hard to schedule.
If its just a chat room that is just there for people to go in and just talk about anything then thats cool, but its hard to make it associated with the forum because its impossible to moderate. Thing can be said which can turn into something MFK does not want to be involved with.
Just my $0.02