Too many buttons, options and clutter.
Too bad you couldn't hit the main page and it shows you all the main forums listed vertically. Click on the forum you want (Wind, Hydro, Solar, etc) and you now have a list of message threads pertaining to the forum topic. Personally, I like expanded threaded displays so I can hit the newest one in the thread, but that's just me. The different message threads are arranged by the last message posted, this way, new messages to an old thread automatically bump it to the top of the thread list.
A good example of this is at bmistress.hyperboards.com
While I understand the board is new, it's one of the most cluttered forum apps I've seen. To me, even though the old board had great threads that get pushed out of sight too fast, it was clean, simple and you could get to the messages with little fuss. This has too many buttons an features, not all of which might be necessary. Additionally, there's no topicx for "TEST" or just a "RANT" so things like this get posted all over the place.
