The way I use the forums might be a bit odd. I pretty much only use the Unread Posts link (my bookmark is straight to that link!) so I can see what's changed since I last checked. I don't go looking into specific sections. In fact, I hardly pay attention to what section anything is in except for when I'm creating my own posts.
But ever since the DC server upgrade a couple months ago my own posts that I've just made will often show up in the Unread Posts. How can it be unread when I wrote it? But it gets worse. Even if I click on them to view them, or if I check the box and select "Mark selected posts as read" they will often still show up for in the unread posts. Eventually after trying multiple times it will "stick" and no longer show up on my unread posts list. I haven't been able to work out exactly what the pattern is, but it seems to be based more on time than the number of times I try to mark it as read. That is, if it's been a couple minutes since I made the post, then marking it as read will usually stick. But if I just made a post within the past 60 seconds then marking it as read is usually a fruitless endeavor.
It doesn't happen every time, but it happens often enough that it's become very annoying. Am I the only person experiencing this? I've been bugging mouser on IRC to fix it for a while but he doesn't know what's wrong.