See my delicious tags for reference to article: http://del.icio.us/andyramsden/qrcode
I have to admit I felt a little cheated by this article as it was below my expectations. I found it quite difficult to understand what they were actually doing. That said it did actually quantify the landscape of students with QR code readers on their phones. Even in Japan, out of 50 undergraduates only 8 had the required hardware and software. This clearly indicates that although the creation and distribution process is getting simpler, we still have a very long way to go before the technology is in the students hand.