Chapter 2 of Larry Weber's Marketing to the Social Web focuses on the changing role of the marketer and how tactics and techniques of old don't work on the social web. The best quote from the chapter is as follows:
"Bear in mind that the social media world is very different from a traditional communications environment. In the traditional communications model, your organization controls content creation and distribution. In the social media world, you have little to no control over content and distribution. Individuals communicate with other individuals and with groups, and groups communicate with individuals and groups - everyone with everyone. It's highly democratic: Everyone has access and everyone can participate. As a marketer, you go to other people's "parties" as well as create your own destinations for other people to come to you."
It's a hard concept for a marketer to grasp - that the messaging as well as the methods for distribution are out of their control. However, once that concept is embraced, marketers can begin to participate and subtly guide the dialogue versus taking a backseat to what will happen regardless.