A London-based 'tech PR' blog post said this week:
When Kelly Brooks starts appearing in ads featuring QR codes you know that the 2D dot matrix bar code technology is close to a tipping point. Brooks features in a Pepsi campaign that has gone live this week and images of her clutching a QR code have featured in most of the tabloids.
It's interesting timing, as QR codes were discussed in a MCG thread on 'Putting web addresses on interpretation' that was in essence about linking from the offline physical world and online content.
While they're not mainstream enough to be a viable solution yet, we could be getting close to the tipping point where QR tags might become a viable way of bookmarking real world objects and locations. QR tags also provide a way of linking locations to online content without the requirements for a location-aware device.