08-12-2013 Matt Cutts has published the latest videos on Youtube with content “ Should I add rel=”nofollow” to links that are included with my widget?”.
Summary: “What should we do with embeddable codes in things like widgets and infographics? Should we include the rel=”nofollow” by default? Advert the user that the code includes a link and give him the option of not including it?”
To learn more you should watch the video below: