commit: 6b2ca8a - #414 (2014-03-05 12:54:44 -0500)
You guys shouldn't take those Matt Cutts videos too seriously. They are meant for beginner webmasters, after all.
First it's Matt Cutts telling it on his cat blog or in a "funny" video
or conference speech and then it's official Google policy a few months
Google hates the open hyspertext. It won't stop until the last free link will be nofollow. Only votes from the proprietary Google Web with strict identity control aka Google+/Google Authorship will count as endersement.