<http://schema.org/image>
<http://rack.0.mshcdn.com/media/ZgkyMDEyLzEyLzA0LzNhL2ZvdXJzcXVhcmVzLmJ0Ni5qcGcKcAl0aHVtYgkxMjAweDYyNyMKZQlqcGc/f666ab1b/571/foursquare-surpasses-3-million-user-registrations-5cb98d6c41.jpg>
<http://mashable.com/2010/08/29/foursquare-3-million-users/>