Alex, it's working for me. In the default theme, Forever Blue, in the middle of the thread status (showing if it's read, unread, hot, or locked), there should be a black dot if you've posted in it. That's from what I've interpretted. I haven't read through the entire FAQ yet nor the vBulletin manual thingies. So yeah, they still work. I don't think that you can disable them
And Andy, we'll have to look into it more... Just allow some time for discussion.