Brion-
Now I know we're supposed to be in feature freeze, but I consider this a bug fix as it's been damn annoying. I've just checked in changes to Article.php, SpecialContributions.php, and Language.php to add a last-user-name check to the rollback link. If when the rollback is activated, the last editor on that page is someone other than it was when the link was generated, it will throw an error message instead of blindly reverting -- usually putting the vandalism back on top. :)
Thanks, Brion -- I had this in my todo list but put it on hold after the freeze. Seems to work fine on test.wiki. I have updated the error messages somewhat -- please take a look. Also, the "edit comment was .." message is no longer shown when there was no edit comment.
Regards, Erik