I’m currently reading Writing on the Wall: Social Media – The First 2,000 Years
by Tom Standage. He draws the line from modern social media and the iPad back through history to roman times.
He makes the interesting point that modern one-to-many mass media is an aberration, and social media is the natural way for humans to interact.
Unfortunately, most web sites today are still built with a one-to-many communication mindset. If you allow your users to interact with your content on your own platform, you know what they are talking about and can participate in the conversation. If you just present static information, your users will communicate in the form of social media graffiti that you won’t notice until you’ve lost control of the conversation.