Maybe I'm being too simplistic here, but if we're talking about why certain number of boxes appear, my understanding has always been that they change to a fixed amount when a user's membership category changes, which happens when they have made a certain amount of posts. For example "Newbie" gets and stays at one box until their post quantity increases to the next category ("Jr. Member"?) at which time they get 2 boxes, then 3 at the Senior level, etc. I don't think there's any more to it than that, just a visual representation of forum activity level. Moderators and Steven get unique colors and maxed boxes due to their role here and to quickly identify their posts in a thread. If it wasn't past April 1st I'd think we were just joshin'.