It looks like it could be her, but here is another photo from the same session with the same blonde person in the back and it doesn't look like Christine in this shot (or like Danny)
http://4.bp.blogspot.com/-PqkLSe3CF2...1600/30166.jpg The topless woman is Ushi Obermaier and that's at the commune in Germany that Peter Green visited in 1970, so there is a link with Fleetwood Mac. Also these pics are from 1969, Christine's hair looked different that year.