I found this fascinating quote today:

With the expansion of the marketer’s toolbox to include social media, marketing is no longer about pushing out one way communications. The marketing world is no longer defined solely by impressions; it’s now a world of interactions. Today’s marketing includes the customer’s voice throughout the process, whether it’s intentional or not. Customers will talk online and comment on a brand’s marketing campaigns, products, services, and even how a company treats employees. It’s not enough to think about how companies communicate outwards; it’s just as important to think about how customers can communicate back, with each other, and arguably most importantly, with new prospects.adamhcohen.com, The New Marketing Funnel, Aug 2009

You should read the whole article.