Vitek: It can happen when someone posts new post but not by clicking "New Post" button but instead clicks "reply" on your post and then deletes your quote. Because the reply message ins't generated by including quote but by clicking reply button.
This is true, but in that case one still gets the little red wedge next to someone's post ... but I've gotten the little reply indicator when there was nothing in the thread except my post and the OP's.
bevinator: On the original topic, I'm convinced that SkyGOGNet really likes Heroes of Might & Magic, because there are phantom posts there almost all the time. The consciousness is almost strong enough to break through into the physical world now!
Interesting, I hadn't seen many until recently in the forums I frequent, so I guess the intelligence is spreading.
bevinator: If an initial post gets downvoted enough to be grayed out, then that entire thread will always be grayed out. One downvote certainly won't do it. This can lead to weird stuff like having new replies in a gray thread, but that's how it works. It actually often makes me MORE likely to check a thread often, simply because I can't be sure if there are any new replies yet.
I guess it is possible for some of them, that the OP had been downvoted enough, but then someone upvoted them so they weren't hidden, but the thread remains greyed-out? Because I could've sworn not all threads which were greyed-out had hidden OPs.