<http://schema.org/topics>
"Alfred,analog,Apps and Software,camtasia,clarify,cloudapp,fantastical,features,flare,app store (iOS) ,mac,marked,OS X Lion,pixelmator,reeder,Tech,Uncategorized"^^<http://www.w3.org/2001/XMLSchema#string>
<http://mashable.com/2011/12/12/top-mac-app-store-apps-2011/>