Heck, it's in the same state it was post-Google, too, when Citysearch was the disruptor. Yelp started out good, probably very akin to where Foursquare is now (clean-ish data, fresh perspective), but tolerated too much garbage, much like Citysearch did, until the user has to over-engineer their search in order to get relevant results that aren't contained in 400 pages, 5 items per page.
Think of how long it's been since Yelp added any filtering criteria. Take a look at their user-photo gallery functionality. Old, stagnant, and ripe for a new generation. However, since sites have been repeating these mistakes for 15 years, there's no indication that any of these are solvable problems.
Think of how long it's been since Yelp added any filtering criteria. Take a look at their user-photo gallery functionality. Old, stagnant, and ripe for a new generation. However, since sites have been repeating these mistakes for 15 years, there's no indication that any of these are solvable problems.