<http://schema.org/topics>
"Advertising,blogging,Blogging Lists,Business,Business Lists,news,content,contributor,features,funding,How To,Lists,Marketing,online marketing,ROI,Social Media,Startups,Twitter,web"^^<http://www.w3.org/2001/XMLSchema#string>
<http://mashable.com/2011/07/04/how-to-measure-roi-content-marketing-strategy/>