Why would they do that one might ask? My interpretation is they "get" that the participation age is largely driven by the social dynamics of individuals and the sum of a crowd. Take for example the Digg thing
. A Sociologist would have known how it would unfold and would have watched it with great interest and perhaps would have interpreted it not as a mob who wanted to take advantage of free DVD watching, but as a crowd who saw one of their basic rights being threatened. I'm in the camp that believes the folks who distributed the DVD key didn't do it for the value of the key -- most of them don't know what to do with it and likely don't care, they did it to make a point: Don't threaten my basic right to speak freely.
A sociologist could be of great value in helping tech companies build a social platform that is conducive to meeting the needs of a crowd as well as ensuring a company effectively contributes to and helps build whatever community it is they wish to be a part of.
Per the CNET article
"Duncan Watts, professor of sociology at Columbia University, where he was director of the Collective Dynamics Group, and author of Six Degrees: The Science of a Connected Age, will lead Yahoo's research in human social dynamics, including social networks and collaborative problem solving.
Watts said his areas of interest include "trying to understand how social networks and communities evolve over time, how people influence each others' behavior and how people find things that are useful."
Having researchers who aren't focused on computer science will not only help Yahoo improve its product and service development, but could lead to advances in the development of technologies underlying the Internet, said Prabhakar Raghavan, head of Yahoo Research."
Smart move indeed, IMHO.