There's some rare and fairly unique material in there, including Joni playing solo at the 1969 Newport Folk Festival, and the showcase performance during Bob Dylan's Rolling Thunder Revue show in 1975. In the Dylan show, Joni would perform songs from her current album 'The Hissing of Summer Lawns'. The archive here includes 'Woman of Heart and Mind', 'Coyote', 'Don't Interrupt the Sorrow' and 'Edith and the Kingpin'.
Also available is a version of 'Shadows & Light' performed with The Band in 1976 that I've never heard before, together with a version of 'Furry Sings The Blues'. The cover versions include Bonnie Raitt singing beautifully on 'That Song About The Midway', Judy Collins doing 'Chelsea Morning' and Don Henley covering 'River'.
There's a free 14 day trial on the archive, so check it out at http://www.wolfgangsvault.com/playlists/joni-mitchell-vault-digging/playlist-325236.html?