<http://schema.org/topics>
"adium,Apple,boxee,Desktop App Lists,Dropbox,Facebook,flock,Google,google reader,hulu,im,Lists,RSS,skitch,Skype,Social Media,social networking,social software,software,Twitter,Video,voip"^^<http://www.w3.org/2001/XMLSchema#string>
<http://mashable.com/2009/08/28/free-mac-apps/>