Most of the time, I want to review a forum or thread for new posts only. Right now I have to either click and read every thread (to make it display as dimmed in the future) or scan each item for the 'last post' time and mentally calculate if it is new. It would be much easier to have a button somewhere (up top?) to just mark the whole thing read so I know when I come back later it will be easy to immediately identify the truly new items.