大众点评网 ("The Masses Rates Web") allows viewers to vote on their favorite restaurants.
For example, pictured above is Hong Kong's 许留山. It got 25 points for its food, 12 for environment, 15 for service and is priced at ￥32. You can bookmark requests, send them to friends, or rate them. And of course, you can add to the pages of comments already there!
Restaurants are categorized by food type as well as city, and if you're a loyal user, you might make it onto the 食神榜 (God of Food Listing).
(The website seems to be expanding this restaurants sharing service to shopping, entertainment, etc as well, but right now, it defaults to restaurants.)
Thanks Ben Chen. Link here.