<http://schema.org/topics>
"Advertising,Apps and Software,Comics,Dev &amp; Design,Facebook,Gadgets,Gaming,Marketing,Media,Memes,Mobile,Photography,Politics,Social Media,Sports,Startups,Television,Twitter,Uncategorized,U.S.,Video,Videos,Weekend Recap,World"^^<http://www.w3.org/2001/XMLSchema#string>
<http://mashable.com/2012/04/23/weekend-recap-51/>