Duncan Watts knows more about small world networks than most of us. That's why we should take note when he challenges some of the key assumptions underpinning the prescriptions of viral marketing:
We imagine information or influence propagating through a network in the manner of an infectious disease. We talk about viral videos and viral media, and we really think things spread this way. What we recently stumbled on is that almost nothing spreads. Instead, the vast majority of all adoptions happen within just one degree of the seed...Research suggests that when we do see big events—things that we call viral—something other than word-of-mouth, peer-to-peer diffusion is happening..Once you get your so-called viral video on the front page of Yahoo!, 100 million people see that. So this is not about viral anymore. This is mass media.