It may happen that you run across a thread that is experiencing one of the failure states we saw in last week's difficulties. The more severe of the two (duplicated subject with "-1" replies showing) is more obvious both from the forum side and the backend, but the other one doesn't really manifest itself until someone tries to read the root post of a thread. If you click a thread from the topic list of a forum and get a page that's empty except for the header, don't panic; back up and try "[View All]" if available. (I haven't seen this happen to a thread that doesn't have enough replies to make that visible; possibly it only happens to "viewmode=threaded".)
Also, if this happens, you could help us out a bit by checking here to see if it's been reported, and if not, posting the URL to the affected thread, so that we can investigate and hopefully fix it up.
Currently known problems:
Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
Eyrie Productions, Unlimited http://www.eyrie-productions.com/
zgryphon at that email service Google has
Ceterum censeo Carthaginem esse delendam.