Perhaps no single book in recent years has had as much impact on the world of network marketing as Seth Godin’s Permission Marketing. Seth’s second book, Networking the Ideavirus (and his recent, Survival is Not Enough) are just as groundbreaking. In this interview, Godin talks about the current revolution in marketing and the secret of how to leverage people’s pre-existing networks of friends—secrets that made Ideavirus the single most-downloaded e-book in history.