I actually do see a difference. Exclusives are the models who go out, do the castings, and they get paid a lot of money to be one of "the girls" for that label. The supers, on the other hand, I see as being a case of them not having to go out and do the castings-they are usually special requests from the designer and you can see that for the Dior Couture show at Versailles posted above, there are a lot of models who would not normally do the couture shows-or runway anymore in the case of Karen, Helena, Linda-but a) it was a big event, and b) big event+big designer=more pull with getting models. Shalom actually does a lot of Dior Couture shows, she's closed two in recent years (Versailles and then the SS 07 I believe).
Many times you will see models doing fashion weeks in their home country who could be put in that second category-special requests, only doing one or two shows and getting opening/closing slots at them, etc. Alice Burdeu was a good example because when she did RAFW recently, she only did three shows-and Alex Perry being one of them, where she opened and closed. Gisele Bundchen I think is exclusive for Colcci in Brazil, I dunno if that is the right one but I know there's one show she does. Toronto FW had a lot of girls who just made it big-Amanda Laine, Kate Somers, and many more, but also getting Coco Rocha to walk one of the shows.
Many times you will see models doing fashion weeks in their home country who could be put in that second category-special requests, only doing one or two shows and getting opening/closing slots at them, etc. Alice Burdeu was a good example because when she did RAFW recently, she only did three shows-and Alex Perry being one of them, where she opened and closed. Gisele Bundchen I think is exclusive for Colcci in Brazil, I dunno if that is the right one but I know there's one show she does. Toronto FW had a lot of girls who just made it big-Amanda Laine, Kate Somers, and many more, but also getting Coco Rocha to walk one of the shows.

Of course she was never big in her teen years however.
Just clarifying exactly what I said.