I gave 5 answers on superuser. One has been downvoted, and apparently no other answer has been upvoted, so I currently have only one downvote. Despite this, I've been awarded the "teacher" badge, which is supposed to be granted only when you get upvoted.
The best I can think is: maybe somebody upvoted one of your replies and then revoked it? (after all, a downvote+revoke awards critic...)
(the numbers don't support the alternative theory of 1 upvote and 2 downvotes)
Oh right, that could also be a case, although it's still a "bug" somehow. The badge should be assigned when the vote cannot change anymore (but I do see the trouble of handling the situation if the comment is edited, thus reopening the change). In the end I think it's not worth the effort, or even calling it a bug.– Stefano BoriniJul 16, 2009 at 21:09
i know i gave a downvote, then revoked it a few minutes later, but i still got the "critic" badge (cast first downvote) about ten minutes later– KipJul 16, 2009 at 21:30