So for example, if you search for a favorite Movie, you'll be displayed a list of most most 'liked' movies by your friends. Similarly music, restaurants etc. In short, Facebook shows up the 'Most' liked visited read or listened data by your friends in your network.
Important Points about this feature are:
1. You can only view the content that is shared with you.
2. Most content is not Public.
3. Every Piece of content has its own audience.
Also, users can volunteer for the beta testing of this feature. All you need to do is hit the sign up button here