In a recent citi report entitled "Weinswig’s Deep Dive: Retail Technology", researchers found that QR (quick response) codes are "gaining popularity and represent a huge opportunity for retailers to engage with consumers." They further site a survey by Chadwick Martin Bailey and iModerate Research Technologies where it was found that half of smartphone owners have scanned a QR code at least once. The citi report concludes that they "expect that QR codes will continue to gain popularity as more consumers become aware of their purpose and retailers improve the content".
QR codes today offer retailers and brands the single most cost effective means to engage the in-store shopper.
You can access the report at :http://www.tradestonesoftware.com/Resources/documents/Citi_DeepDiveRetailTechnology_January2011.pdf