I think the "General Discussion" section on most forums are the most active section since almost anyone can relate to the topics in the general chat section, so they usually get more replies from a larger group of members.
I think forums who get more of their traffic and posts from post exchanges, paid posting services, etc are more likely to have a more active offtopic sections since when I did more post exchanges, I notice some of the forums have subsections which don't have many topics which I can relate to, so I just post in the offtopic sections to finish my post exchange. I think a lot of the members which I got from post exchanges also post in my offtopic section because they can't relate much to my forums topic which is "asian pop music and entertainment", but need to finish my post exchange so they post in offtopic and other general topic forums like gaming, and movies.
But, forums which are about saving money with coupon codes are more active in the coupon codes section.
I find that the forum games section on most forums is the most active. Other than that, the general discussion is probably the most active. Depending on the genre of forum I guess.
