This document discusses social media and its importance for marketing. It notes that marketing is no longer just about corporate websites and Google, but also social media. It provides examples of how blogs succeeded because they allow free self-expression and are easy to use. Case studies show how customer complaints on blogs can drive traffic and comments. The document also breaks down types of internet users and their level of participation in social media, from creators to spectators to inactives. It emphasizes sharing as a dominant online activity.