Last week, as a result of some upgrade to the Maps, things were pretty flakey. Most of the weirdness was fixed that day but QR codes remained non functional into the later part of this week. Apparently the Google url where the QR codes were being directed: http://maps.google.com/m/place/… was not working properly and not being redirected.

Whatever the problem, it has now been repaired and QR Codes seem to once again be functioning.