Currently it's possible to see all the attributes, e.g. on http://classic.musicbrainz.org/show/artist/relationships.html?artistid=491558&expanded=1&all=1 you can see that she performed vocals, background vocals and guest vocals, that she plays the erhu and that she wrote and translated lyrics, but http://musicbrainz.org/artist/dded0177-e235-474e-8529-a812b89f806c/relationships just shows the relationships without any attributes