From the VISA U.S.A. Operating Regulations:
6.2.A.7.b An Issuer that enables Non-Visa Debit Transaction processing on or after July 1, 2008, and does not require that all such transactions be authenticated by a PIN must:
Clearly communicate to its Cardholders at the time of implementation of such processing or at the time of issuance, and on an annual or more frequent basis thereafter, that it has enabled Non-Visa Debit Transaction processing and that it does not require that all such transactions be authenticated by a PIN
No, I didn't lose my mind. It got scared and ran away.