This week, Apple got a rude awakening with its initial foray into the world of local search and mapping. The media and user backlash to their iOS upgrade which removes Google as the maps and local search partner and replaces it with their own application (built on licensed data) demonstrates just how important the local scenario is to the mobile space.
While the pundits are reporting various (and sometimes amusing) issues with the data and the search service, it is important to remind ourselves how hard local search can be.
For example, if you search on Google for Key Arena - a major venue in Seattle located in the famous Seattle Center, you will find some severe data quality problems.
Google has confused Key Arena with Center House (another nearby venue) - we can see evidence of this in the photo. Consequently, the Zagat reviews for the two entities are mixed up. It seems that they have also confused the arena with the Seattle Center in general (judging by a reading of the reviews). Finally, the location of the arena (the push pin on the map) is in the wrong location.
Google also links data to reviews found on the web. The first link at the bottom of the g+ page for Key Arena links to Trip Advisor's page for 'Chihuly Garden and Glass'. All told, Google has over-matched at least four entities.
One of the ironies of local data conflation is that landmark entities (like stadia, large complex hotels, hospitals, etc.) tend to have lots of data (everyone knows about them) and lots of complexity (the Seattle Center has lots of things within it that can be confused). These factors conspire to make the most visible entities in some ways the entities more prone to problems.