As a keen modeller in my youth I like the idea of a "modelling" forum, but don't think it's mainstream enough to warrant it's own forum.
The cafe Pilot's lounge would be the place to discuss anything to do with modelling, and I, Kevin and Jared to name but a few have posted photos of our models in the Photo and camera forum.
Nice thought though Matt :)
Whist I agree it is not that main stream, there are quite a few of us. Posting in the photo forum or the cafe poses one small problem. The ability to look back at what has been posted before. With these two forums, the subject matter is so large, that it is easy to lose a particular thread that you want for reference. Model making is all about that. Also, I have posted modeling questions before and due to the large turnover of posts, the thread that I have started flies down the page before I can get an answer because admittedly, the majority of members are not interested in this area of aviation (though I do build 1:8 scale cars too ((Pocher))
Matt