Backstage, which will appear as a channel tab, gives producers a new way to share content with fans. But it will also allow subscribers to comment with (Backstage-only) video, photos and other "rich replies," according to VB. That's along the same lines as Twitter, which supports links, videos and GIFs. It could also open it up to more abuse, though it's hard to top a YouTube comments section for that.

YouTube is still by far the most popular video site on the net. Facebook recently reported that users watch 100 million hours of video per day, but YouTube reportedly serves up over 500 million hours daily. There's often not much reason to linger on YouTube (other than watching more videos), though, so the site is likely hoping the social aspect will convince viewers to stick around longer. Backstage is expected to arrive by the end of the year, starting with select, influential YouTube accounts.