Back in my days as a children's book editor, my superiors caught on to the fact that teenagers were using the Internet to gossip about each other, and thought it might be nifty to develop a series of books about an anonymous high-school blogger who gossips about her classmates. The concept was passed on to me.
I feel like 'Gossip Girl' isn't really 'Gossip Girl' anymore when they're away at school because they don't go to NYU; they go to, like, Yale and Brown. New York City is just as much a character as anyone else in the books, and I was really sort of reluctant to show them off in their separate college worlds.
I used to be an editor and I was editing young adult series. I didn't really like the books that I was reading, so I decided that I would write a book about something I'd want to read if I was 16. It turned into a Cinderella story... I developed a proposal and the characters of 'Gossip Girl' for my job.