People judge you by your associates, and the new social media are making that a very big marketing issue. Marketers now have to figure out where their customers are congregating, go there, and act like they belong.

ChiefMarketer.com: No Escaping Online PR.
By Sherry Chiger 2006-Oct-31

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The tools of Web 2.0 can [give] companies more control in their ability to talk directly to consumers. For instance, (Product) Red, a not-for-profit brand founded by Bono to raise funds to fight AIDS in Africa, has a Website (JoinRed.com) and has been promoted heavily in ads from commercial partners such as the Gap. But within a week of adding a MySpace page, visits to JoinRed.com rose nearly 80%.