For anyone who thinks to check here… yes, the ZBB is having problems, I know, and I’ve submitted a ticket with Dreamhost.
(Basically you can look at most threads, but not all, and you can’t post at all. I can’t log in as admin so I can’t even put an alert over there.)
More bulletins when I know more (also on Twitter).
Edit: Looks like it’s fixed. Dreamhost, with moderate usefulness, told me I should optimize the database and maybe repair tables. They suggested phpMyAdmin, which didn’t work. But their page also suggested using SSH, and that worked.
The problem may have been intermittent, I can’t tell, but I can say that I couldn’t post yesterday and now I can. So in good IT tradition I’m going to close this up as resolved.