In order to make sure that I didn't miss anything, I often read from the "Recent Posts" or "All Topics" views.
I've often thought that it would be a nice visual aid if some, or all the forums had theme colors to differentiate their posts in this contextual view. I.e., posts in the For Sale and Want to Buy forums could be shaded green, Layout construction could be brown, Traditional O could be orange, etc. That way I know what I'm reading and responding to.
You could also possibly add a flag where Forum readers could alert the moderator if they think a post was started in the wrong Forum, or if the discussion veers in a direction that would make the thread better placed in a different Forum.
Disclaimer: I've never been an admin, and I'm not sure if it's even possible to implement these suggestions. Just putting some ideas out there for consideration.