Foursquare does this. Explicitly shows you your 4sq/Swarm friends' relationships to the place (have they been there? saved it to a list? said they 'like it' or

Foursquare does this. Explicitly shows you your 4sq/Swarm friends' relationships to the place (have they been there? saved it to a list? said they 'like it' or 'dislike it'?), and then in the list of tips/reviews surfaces the stuff your friends have left before others. When searching, you can even filter for "only show me places my friends have been".