<http://schema.org/description>
"The actual cost of an advertising campaign on Twitter has always been somewhat shrouded in mystery with large campaigns run without direct figures revealed.\u00A0Well now they have and ..."^^<http://www.w3.org/2001/XMLSchema#string>
<http://thenextweb.com/twitter/2011/06/13/inside-twitters-ads-120000-per-day-for-promoted-trends/>