The tagging automatically 'corrects' to whatever is put in the Last.fm database so be prepared to have some stuff automatically be scrobbled wrong anyway.
I don't tag anthing... xD The only thing I hate is the redirecting to the wrong artist pages. That can be bothersome. ;; (Am still getting used to it ><) But it's fun to see which artists come out on top of your listening and finding new music. High rec either way~ ^^