As reported in this article, Foursquare has started selling ads that can be targeted based on where someone has checked in.

It’s an interesting (if not unexpected) new frontier for the platform. As ads in the digital and social spheres become increasingly more targeted based on any number of criteria, it seems only logical that if you’re actively telling an advertiser exactly when you’re physically located somewhere that sells their goods, they would try to influence your purchase decision while you’re there – and likely pay handsomely for it.

Obviously the possibilities for such advertising are nearly endless. The demand for this targeting could become particularly fierce among brands in the food & beverage industry, or among retailers that sell competing brands under one roof. As a sort of digital POS display, it wouldn’t be surprising if participating businesses began to offer such promotion as an available premium to their vendors.