One interesting facet of all these recommendation and ratings systems online (Yelp, Goodreads, Rotten Tomatoes, etc.) is that they don't provide a key value tha

One interesting facet of all these recommendation and ratings systems online (Yelp, Goodreads, Rotten Tomatoes, etc.) is that they don't provide a key value that in person recommendations do. When a person recommends a restaurant they are attaching blame for the restaurants performance to themselves. Its performance is a reflection on them and their credibility. It is very hard to replicate this on the internet, a place where people can suggest things with very little responsibility. If I strongly suggest a movie to someone and the movie sucks, I can be blamed for that. I don't know how to replicate that comfortable eschewing of responsibility that in person recommendations provide.