Unlike Zagat, which has its own volunteer army of reviewers, Boorah scours reviews from sites like Insider Pages, SFGate, and blogs, and extracts content from them. The site parses all the data and assigns scores for food, ambiance, and service for each restaurant.
The site has a relationship with OpenTable (my favorite Web site ever) and will let you make direct reservations for restaurants that take them.
What I liked about Boorah: it has a very good search engine, with fields specific to dining out ("Romantic," for example). It also has a great "Open Now" search category.