Yelp did release Worldmaps which provide a interesting view on the data the company collects.
What is Yelp? Yelp offers you over 39 Mio reviews, those reviews are provided by users of Yelp (called “Yelpers”) after they experienced a hotel, restaurant or any other local business.
Yelp did ealier in JUly release Yelp Wordmap: a map showing density of keywords used in Yelp reviews to reveal fascinating patterns of local discovery. Day one 14 cities ave been made available: Austin, Boston, Chicago, London,Los Angeles, New York, Paris, Philadelphia, Portland, San Diego, San Francisco, Seattle, Toronto and Washington DC.
Yelp did recently release maps that show based on their review key words that are most used in certain areas. This can help you to for example to find or avoid touristic places like shown on the NY map below
or go to places which are more related to cheap in London: