[rapind]

The big problem with these type of review sites is that it's pretty difficult to guarantee review authenticity. A competitor could post a bad review of your business, you could post a shiny review of your own business, nimrods who've never purchased anything from you can write a bad review, etc.

When there's more money involved, and when the business community being reviewed is more specific and defined it has proven to be very useful and successful. I.e. Angie's List.

Anonymous web reviews were useful once upon a time before the web grew up, and marketers started gaming the system en masse.

What I'd pay for is a sort of premium search tool that guarantees the authenticity of everything it serves up.