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Oink looks to be a mobile application (Rose didn't specify) where people find things--like wine, restaurants, chocolate, tea, roller coasters--and rate them (thumbs up or down, or thumb to the side for so-so, or a heart for something that is just spectacular). Users grow their reputation (or "cred" to use Rose's lingo) by using the tool, and based on the volume of ratings in particular areas.
So if a user sees someone has rated the latte at a particular coffee shop highly, it comes also with what that person's reputation is in rating coffee. It seems to me that it should somehow allow others to have some input into that person's reputation, but perhaps that can come later.
Users can also see what those people in their social graph like (Rose didn't specify which social services tie into Oink, but the web site lets users log in with their Twitter accounts). The service will begin with recommendations and even geo-fencing, so users can make a choice about what to pursue based on where they are, and where that particular item is.
It's best to see Rose demonstrate this, so watch the short video below: