I deleted my databases and to my suprise I could still sort on artis, track etc. When playing a song I saw the correct tag info in the music overlay.
The load id3 from file option is OFF in settings.

(could this also be the cause of the slow performance on music?)

h4. Additional Information
I did the same,
you can press the 'sort' by button but thats it
if you look better you'll notice you cannot sort on artist, album,...
However when you PLAY the song, then the ID3 tags for THAT song gets loaded. Is this a bug? i think not