One great new feature brought to us by vBulletin is the old and new post document icons next to each post. I've always longed for a feature that would allow me to mark which post of a particular thread I had last viewed, because I often find myself backtracking over posts I've already read when I return to a thread I haven't followed for awhile. This is pretty much the feature I wanted. In other words, when you first view a thread, all the small document icons next to each post are orange, reflecting their unread status. However, when you return to the thread later, the posts that were previously loaded have white document icons, and only the new posts have colored icons. Bravo!