Google is delivering window stickers to the 100,000 most searched for business. The idea is that the businesses will place them in the window allowing passers by to use their mobile devices to quickly access that stor or restaurant's Google Places page for more information about them.
The use of Metatags to add deeper informaiton to a location is nothing new. I participated in the Yellow Arrows project a number of years ago, leaving yellow arrow stickers all around Atlanta with meta codes on them accessible via SMS textmessage. The difference here is that the yellow arrows were a single persons perspective of the location, where the Google project is the Google view of the place. There is less personal input and interest and more rote information... which could be very valuable to most.