
"...user reluctance (or ignorance) which is preventing more-widespread use."
REALLLY? More likely the fact that despite what Visa says, not all that many cards actually support the contactless feature (ref: Nationwide, Santander etc) and it's still not 100% reliable. Most retailers still tuck away the contactless component of the reader (lookin' at you, Caffe Nero) and the look of utter surprise on the face of the cashiers suggest that they very rarely see contactless payments.