installed amarok and played around, except that its a rich gui – which i usually try to avoid it seems awesome, last.fm support, very cool, also some real nice features like dynamic playlists
another feature is synchronization with mp3 player, so you can eg. create a dynamic playlist with your favorite songs (highest play count) and sync those to your mp3 player (=mountpoint in my case)
there is also musicbrainz support – which isnt so nice for mass tagging, actually there is no mass tagging :/ will try to find something the next days..
