Maybe there is a risk for at least some users that they will become so enmeshed in online life that it takes precedence over the complex interactions of the real world.

One person who believes it may be cause for concern is respected British neuroscientist Susan Greenfield.

Recently she speculated that social networking sites could destroy real-world relationship skills.

"I often wonder whether real conversation in real time may eventually give way to these sanitised and easier screen dialogues, in much the same way as killing, skinning and butchering an animal to eat has been replaced by the convenience of packages of meat on the supermarket shelf," she said.

In a recent essay, literary critic William Deresiewicz bemoaned the loss of solitude in our lives.

"Technology is taking away our privacy and our concentration, but it is also taking away our ability to be alone," he said.

_ Nick Galvin/Sydney Morning Herald