<http://schema.org/topics>
"digg,friendfeed,james surowiecki,news,opinion,Politics,San Francisco-San Jose,Social Media,Tech,Twitter,Web Apps,crowdsourcing,YouTube"^^<http://www.w3.org/2001/XMLSchema#string>
<http://mashable.com/2008/09/15/wisdom-of-the-crowds-isnt-the-answer-for-everything/>