The part that uses the Social Graph API: http://code.google.com/apis/socialgraph/docs/ http://code.google.com/apis/socialgraph/docs/ is based on crawling XFN re

The part that uses the Social Graph API: http://code.google.com/apis/socialgraph/docs/ http://code.google.com/apis/socialgraph/docs/ is based on crawling XFN rel="blah" links from all over the web. The canonicalisation layer that's used is opensource: http://code.google.com/p/google-sgnodemapper/ http://code.google.com/p/google-sgnodemapper/