This forum has the worst spam problem I have ever seen. I seriously suggest changing your sign up policy to reduce this.
Also I think the number of subforums could be reduced. I think it is confusing and a lot of things fall under multiple categories, so how do you know which section you are meant to post it in?
I think a lot of stuff just would not be read at all, because not everyone will view every single category, especially when the first half dozen posts in each category are spam. This would also reduce the amount of spam a great deal, if you halved the subforums, you would halve the amount of spam.
I know I haven't been here that long, but these things are some pretty fundamental flaws.