Pat Kinsel with a smart post on why local discovery is a tough tough business.

Why is local search and discovery a flawed concept? Simple: query volume.
No matter how compelling or timely a service’s results are, people just don’t ask themselves “Where should I go right now?” that often. People do rely on directions and place lookup as utilities to get themselves to an already intended destination, but they just don’t walk around town desperate to discover where they should visit next. Look at Foursquare. In its early days, it was a game and drove usage accordingly. As they’ve abandoned the game elements and emphasized their search and discovery capabilities, usage has declined precipitously. People just don’t need to ‘discover nearby’ that often.
Search businesses require massive query volumes to succeed. How often do you ask yourself, “what should I do this afternoon?” or “where should I visit right now?” Once a month? Every week? With these usage patterns, a service would need hundreds of millions of users to have a meaningful, monetizable search audience.

More interesting thoughts within, including why startups focused on that space make for tough acquisitions.

It seems likely the frontrunners to succeed in this space are players that wrap local discovery inside a local directory service, like Yelp or Google Maps/Waze, though I'm glad a startup like Foursquare exists to try and crack this nut.