https://musicbrainz.org/ws/2/artist/1283f619-2789-4892-af46-29a13e5cca5b?fmt=json uses "name" to refer to the artist name.
https://musicbrainz.org/ws/2/release-group/0c00792f-1022-4a23-8eb6-d1d94ca7564c?fmt=json uses "title" to refer to the release group name.

The website uses "name" for both (http://beta.musicbrainz.org/artist/1283f619-2789-4892-af46-29a13e5cca5b/edit and https://musicbrainz.org/release-group/0c00792f-1022-4a23-8eb6-d1d94ca7564c/edit ), as does the database (artist.name which links to artist_name, release_group.name which links to release_name).

It would be nice if entities were consistent. I'm guessing we can't change the XML WS and I dunno about the JSON one, but either way, if we can't, it would be nice if we can make it consistent when we do /ws/3.