Yelp combines local reviews and social networking functionality to create a local online community. Adding social web functionality to user reviews creates a de-facto reputation system, whereby site visitors can see which contributing users are the most popular, respected, and prolific, how long each has been a member, and which have interests similar to theirs. Strong peer feedback mechanisms and the featured placement of popular reviews on the site and in local newsletters help motivate contributors. Yelp also applies a “First to Review” reward system to create a competition …