Leibovitz has kind of put herself out there as a celebrity photographer hasn't she? (There are a few others as well, but the one name is not coming to mind and I have one of his books from years ago...) And as a portrait artist, I think she does a wonderful job of putting people at ease to get an image that looks the way it does. I don't think that is riding the coattails by any stretch, not everyone can work with celebrities, and of those who can few are able to get the kind of results she does.
Sorry, I have always liked her stuff.
As for the girl, there will always be controversy, I remember when the pictures of Alexandria Kosteniuk came out and lots of folks were up in arms about that too. There is a power a girl/woman/lady/female person whatever you want to call them have in their sexuality. Showing it off, or threatening to do so, teasingly revealing a shoulder or a wrist ankle, thigh, whatever... There is a lot in that. And even in the "nude" photograph, she is pretty much completely covered by that drape thing.
And everyone gets naked on the cover of Vanity Fair don't they? Madonna, Demi Moore, Lindsey Lohan, Keira Knightley, Scarlett Johansson etc... But it isn't like she is posing for one of the Sophisticates, it's Vanity Fair not Maxum, Playboy, Penthouse or Hustler after all.