Shelf Labels are already being used in stores all across Europe and in South America. Using Bridgestone's QR LPD epaper and Eink and LCDs.
http://www.pricer.com/ http://www.bridgestone.com/corporate...010090201.html
A friend of mine works for a competitor to Pricer here in the states and they just started another project for a South American chain. They are also working with one of the bigger chains here about ESL. They are currently evaluating the Bridgestone, Eink and Sipix products