I have an account on server33 where I set up a MediaWiki site this weekend. The MediaWiki uses MySQL.
What I experience, and this is confirmed by other users too, is that it runs terribly slow. There does not seem to be any similar problems with loading regular HTML/PHP pages without database, so I suspect something with MySQL. Are anyone else having similar experiences?
(URL http://www.crusader-kings.com/wiki/ if you want to test...)
Edit: Spelling, URL