American Idol is an ARG
It's really hard to explain what I do. I work in an industry so new, that even while several million people have actually been involved in ARGs, (or immersive fiction or interactive experiences, or whatever you want to call it) far more haven't. It's a little like explaining movies to people who have never seen a movie or TV. "It's like a cross between a book and a photograph. The photographs move." People would think they knew what you were talking about, but they wouldn't.
Actually, American Idol is a very primitive form of it. Because the viewer actually, in the most limited way, touches the outcome. Viewers vote. Those votes affect who wins. Much to the pleasure of the show is seeing if the state of Hawaii votes for the girl from Hawaii, even though she isn't the best one up there. Or if the teenaged girl vote really swings it for the cute guy.
It's an extraordinarily popular show, with live events in several cities across the U.S., which uses non-television technology (that is, phones) as an essential part of it's story telling mechanic. Next, American Idol needs to allow you could send you email address in and your favorite contestant would send you out an email before each competition talking about how they feel and who they think their competition is, and what rehearsals have been like.