I like the active topic button and the ease of keeping up with the current flow of the board. The best feature is, of course, the posters themselves. They are what makes it tick.
I would like to see an active topics on the bottom of the page or just a back to top button. Not too patient with scrolling back up.
The moderation of this site has to be mentioned too because without it, things would go down hill fast, I'm afraid. So thanks, mods.