Google has sent out 100,000 window stickers to US businesses, proclaiming them to be Favourite Places and providing a QR Code for a quick link to information and reviews.

The QR Code is a variant on the traditional barcode, and readable by the majority of smartphones using the camera, the codes sent out to businesses link to a Google Place Page which can contain opening times and the like, along with customer reviews in a distinctly Yelpish style and nearby photographs.

Google reckons you'll be walking down the street and see one of these Google-branded marks in the window, run up a QR Code client and use the camera on your mobile to connect to a page containing opening times, business information and user-generated reviews, not to mention the all-pervasive advertising which is the point of the process.

For the hard of thinking Google provides an explanatory video:

That means Google can advertise to people who weren't even planning to use the internet, who visited Google in cyberspace in response to a physical manifestation of the Mountain View brand.

Businesses are at liberty not to put the service mark into their windows, and those with poor reviews will probably choose not to, but Google will be maintaining a Place Page on them anyway accessible through Google Mobile Maps. It's easy to imagine routinely checking restaurants and hotels against the Google Place Page, with the associated transfer of trust and reliance on crowd-sourced reviews.

That might be a marvellous thing - rather than relying on brands (such as Premier Inn, Pizza Hut or Starbucks) one could find better local alternatives, assuming one trusts the reviews on Google. But it also makes it very difficult for competing services to get a foot in, when there's only so much space available in the business window. ®