I've only noticed this happening today. Whenever the General ODP Issues forum shows new posts and I go into the forum to look at the new posts, all of the posts in the thread are marked read. Kind of weird.
It did that to me a couple of weeks ago, after I'd come back from a week's holiday and there were lots of posts waiting to be read. It cleared itself after I made my initial foray into each forum, and it's working fine for me right now.
