eMarketer predicts brands to spend $1.8 billion on social networking sites by 2010.

Marketers will spend an estimated $280 million in the United States to advertise on MySpace and its competitors in 2006.

"If companies can go even deeper to develop marketing efforts that fully embrace the one-to-one-to-many nature of social networks, ad revenues will soar. And this way of advertising will spill over into other channels. The underlying concept will influence the way advertising is done in all media, not just online," says Debra Aho Williamson, senior analyst and author of eMarketer's new report, Social Network Marketing: Carving Out Some MySpace.