This raises several important issues. The first is that most people don't review things. No matter how easy it is the vast majority of the population just won't do it. The simpler you make it the more that will but the simpler it is the less useful it becomes. This has several important implications. - It makes local hard to scale because your audience size is that much smaller that reviews are far less reliable both…
I think social search has value if we define it differently. In other words, I agree with your assessment. The thing that is social, is search, and has value is something more implicit. It observes the behaviors and decisions of other people, perhaps your friends but perhaps not, and infers recommendations from those. Amazon and netflix already do this in their domains to great success. It will become more prevalent. This is not what most people think of when they say "social search," and this is not the thing that you are (rightly) deriding. But I would imagine that in a decade, this is what will eventually be described with the term "social search."