The New-York Times research lab is developing an application that allows to visualize the dynamics of social networks. How some people serve as linchpins for the diffusion of information.
Have a look at
http://www.nytlabs.com/projects/cascade.html
there is a video that shows better than any words how that works. It is astounding. The information diffusion cascade is shown in real time. You can understand how it spreads (or not). No doubt we are now in the midst of the Fourth Revolution!
