Forktips
Overview
Forktips' design is meant to increase activity in every aspect. It integrates with all the major social networks, simplifies the review process, and is completely objective. Every action on Forktips is social. The attrition rate of Foursquare is undoubtedly high (same with Yelp and all the others) because registration is required & you must be in the restaurant to interact... but you're looking at a Foursquare without any end-user restrictions!