Consider also that Facebook has orders of magnitude more information about its users than Twitter and you can begin to imagine that Facebook ought to be able to charge more.
Although the process was unwieldy, those who worked on Ceefax during the pioneering days were conscious that they were taking part in an information revolution of some magnitude long before the world wide web arrived on the scene.
Through the updated Open Graph (the API tool other websites and application developers use to talk to Facebook), Facebook is now collecting a magnitude more information on people using the service, potentially when they are browsing the web outside of Facebook, but with sites that themselves talk to Facebook.
It has also held that materiality of contingent or speculative events or information depends on balancing the probability that the event will occur and the expected magnitude of the event.