I may be in the minority here, but having watched several forums, (UT sports, fishing, BBQ, etc.) the concept of having multiple boards for various subjects works OK, but only OK. The forums I find are most successful and easy to both moderate and participate on are the ones that allow various topics to be posted into one forum. What happens when folks are only allowed to post on certain subjects in certain places is that people invariably will merely forgo visiting the other, (lesser visited) boards on that forum and stick to one main board. People are typically those that don't want to be required to take extra steps. If they're "friends" with many of those on one board, then that's where they'll remain.
I'll give you an example. I have been on OBs for years. I don't post religious/political/op-ed type posts. I don't go to the Corral. I have been there a few times in passing, but really have no desire to go there. Most of the folks I associate with are on the 40.
Another example is on one of the fishing boards I am on. The "recipe" board really took a nose dive, and now most folks post recipe threads in the main fishing board.
If the owners here are looking to further build upon the "community" atmosphere, then require an OT or some sort of tag and keep most of the posts on the main BoB board.
My 2-cents.