So many similarities. I loved the movie because it was so much like Ugly Betty. Andy is Betty, Miranda is Willy, Emily is Amanda, Nigel is Mark and the only one missing is Daniel.
You may not realize, but original version of Ugly Betty, "Yo soy Betty, la fea" was on television in 1999, 4 YEARS before the novel TDWP, 7 YEARS before the movie.
So you see, The Devil Wears Prada was modeled after Ugly Betty, or at least the original Ugly Betty.
The devil wears prada was a scathing fictional attack on Anna Wintour, written by a former employee. Two original things that Ugly Betty has used as a source :) All great though.