Very interesting. As with anything like this it would take time for adoption of the new hardware. Also for smaller local businesses to implement it they would need their own app, and their customers would have to care enough about their specific store to install the app. Larger chains would benefit more from this possibly. However most of the people shopping at the larger chains would most likely be running Android, and probably a version prior to 4.3.
There are quite a few barriers to this becoming a big deal, but I am curious where it will go, and if it can be used for things besides welcome messages when you enter a store.