I am collaborating with Robert Scoble on a new book, The Age of Context. It is about the next phase of technology's relentless advance.
Our opening chapter deals with five converging forces:  social media,  really smart mobile devices,  sensors,  Big Data and  mapping. We argue that the confluence of these five forces creates a perfect storm whose sum is far greater than any one of the parts.
Following is an extract from the book. It is an extremely brief history of social media, plus a look at what it has become in an amazingly brief period:
“Social media …has been the most disruptive of our five forces. It is also the youngest. In 2005, when we started researching an earlier book extolling its virtues, there were less than 4 million people using it and many business people dismissed it as a passing fad. By 2012, there were nearly 1.5 billion people using social networks on a regular basis....