Today's definition (not the 1992 definition) of a supermodel is a model who's developed enough of a reputation and an impressive enough portfolio that 5 or 6 years after their peak of success, they're still hired for big shows, campaigns and editorials.
Natalia especially has had countless features, full on multi-page articles about her career and her life in a few different magazines....if that doesn't warrant the term supermodel, I don't know what does.
you can't take the term that seriously anymore, have you heard about Supermodel Caprice? Supermodel Sofia Vergara?
I can see what you mean but that's pretty much the definition of a Top Model, to be a Super you need to have more than a decent portfolio, you need to be a star, to have star appeal and the models of this century lack of that, the last model who took advantage of the concept was Gisele Bundchen.
Natalia has not even achieved the 10% of what Schiffer did so I don't think she deserve to be ranked as a Super with her in this Vuitton campaign. it would be Supermodels Stephanie, Claudia, Naomi and Eva + fashion models Angela and Natalia.
there are levels, I think