<http://schema.org/description>
"The idea of build social activity around ebooks is starting to gather steam. We've recently seen Readmill launch as a kind of 'Last.fm for books'. Now OpenMargin, which launched in ..."^^<http://www.w3.org/2001/XMLSchema#string>
<http://thenextweb.com/apps/2011/10/31/social-ebooks-service-openmargin-opens-to-all-turning-books-into-conversations/>