Broadening online worlds could help maintain and improve cognitive abilities in old age.
Conor Friedersdorf recently put forward an interesting question: At what age will you stop using Facebook? Many of the college students, now twentysomethings, who made up Facebook's original user base may already be feeling the fatigue. But it may be through other groups of people, for whom the site was never specifically intended but have nonetheless been discovering it in droves, that Facebook may find new ways of remaining relevant.
For the rest of the story: http://www.theatlantic.com/health/archive/2013/02/study-facebook-may-improve-memory/273439/