I like the forum layout, but maybe that is just because I'm used to it. I have met some people who said they would visit more, but they couldn't figure the forum out. It seems pretty easy to me, so I dunno what they couldn't figure out.
It did take me a while to figure out that the "Forum Index" tab was actually clickable, and not just the items in the drop down menu being clickable. That helped a lot when I figured that out.