I was looking through the Dresden Files RPG forum and I notice a few things:
1) A number of patterns / types of threads
2) there are 978+ threads on a relatively new game
3) threads get buried very quickly
It is good the forum is so active, but it can cause "problems" as well. (I know of games out there that have been around for around a decade that never had this volume of daily activity and total maybe 3x the post count all told)
Where the problem comes in is that posts get buried faster than people can look at them, posts and questions get duplicated more, and posts get lost very easily.
A few buckets (sub-forums) within the category could help immensely, probably one for cities, one for magic & items, one for creatures & characters, and one for general or some other set of groupings. Separating out cities would help encourage "group" effort and suggestions by making them easier to find and track. The rest separate the general patterns and distributions effectively reducing post count in each to 1/3rd to 1/4th current total. That would help slow down the post lost rate.
Not certain if it is doable or advisable, but it is my comment from the peanut gallery.