<http://schema.org/topics>
"brizzly,news,features,HootSuite,klout,Lists,mapmash.in,Mashable,monitter,paperli,polldaddy,publitweet,quoteurl,seesmic,Social Media,tlists,trending,trendistic,twapperkeeper,tweetmeme,twello,twitpic,Twitter,Twitter Lists,twtpoll,Web Apps,wefollow,yfrog"^^<http://www.w3.org/2001/XMLSchema#string>
<http://mashable.com/2010/07/25/improve-twitter-experience/>