The deleted scene shows Miranda's inebriated husband making a fool of himself and Andy stepping in to distract from the debacle. As Andy listens to a man blather on, she catches eyes with Miranda, who does something so un-Miranda-like, it literally ruins the whole film—she mouths,“Thank you.” Gasp!!
In the real final cut of the movie, however, Andy (Anne Hathaway) is stuck at the Met Gala-esque event with Emily (Emily Blunt), and they're both expected to feed Miranda names of important people. Emily slips up and forgets someone's name, allowing Andy to come to the rescue and glide into her boss's good graces. End scene.
Thank goodness the editors cut that scene, because it has no place in the cinematic perfection that is The Devil Wears Prada.
That is all.