Do you add them to a forum? They can be good for enjoyment to the members, and to increase post count, but Google doesn't like useless posts with no content.
I have one and it doesn't really get used.. I think that it is fine to have one just as long as they don't account for most of your forums' activity.
I have one, and it's the most active section at the moment. I think it's quite important for post boost and for members to relax and have fun. of course, we need to maintain number of posts outside that section too. ^^"
