In the magazine world, the year's biggest moment is the September issue. It's filled with the most advertisements, the most lavish photoshoots and, of course, the most A-list cover stars. Standouts so far? Rihanna nailing it on W and Audrey Hepburn's granddaughter Emma Ferrer making her debut in the glamorous pages of Harper's Bazaar. But Vogue US' September cover has just dropped and changed everything. Here's why the fashion pack is buzzing: 

1.) The Mario Testino-shot cover features three of our fave models, who also happen to be BFFs off-camera: Joan Smalls, Cara Delevingne and Karlie Kloss. (Side-note: the fold-out features other catwalk queens Arizona Muse, Edie Campbell, Imaan Hammam, Fei Fei Sun, Vanessa Axente and Andreea Diaconu.) This is the first time in 10 years that Vogue decided to feature models instead of a celeb for the coveted September cover. Many feel that this marks a turning point — and the birth of a new supermodel generation. 

2.) Vogue dubs these stunners "The Instagirls." What does that mean? Well, according to a behind-the-scenes video (which is adorable, BTW), the concept of an old-school model is a bit passé. These days, it's important to build your personal brand and engage with fans in order to take it to the next level, which they all accomplish via social media (hello, Cara's Instagram!). No matter who Anna Wintour decides to put on the cover of the Fashion Bible next, we're giving her serious props. *Insert an emoji round of applause here*

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