Affinity Layer
All your likes are belong to us.
Layer 1: Who's who, Identity,
Layer 2: Who matters, who's interesting, who's reliable... Afinity
The Nerd'ster demos this using "follow contexts" that allow following people for different contexts, such as music, news, books, local, under30, and so on..
The idea is to allow services leverage your affinity preferences across services.
Read the New York Times and like someone's feedback? See their comments highlighed on the Wall Street Journal.
Report a positive interaction with an Ebay seller? Have that reflect upon them as an Uber driver.
Know someone in real life? Trust them? Respect them? Express that so that we can all leverage your judgement.
(This necessarily relies on the ability to know who's who and to identify individuals, which is accomplished in the Identity layer.)