The Payment Card Industry Data Security Standards (PCI DSS) were put in place by the major card brands -- including Visa and MasterCard -- to ensure that retailers take sufficient steps to protect customer card data.
The card brands, particularly Visa, have a vested interest in demonstrating that PCI makes customer card data more secure. If a PCI-compliant retailer still gets breached, that's a lot of egg on Visa's face.
So what happens next?
First, the card brands will likely conduct an investigation to determine if the retailer was compliant at the time of the breach. As I wrote in a recent cover story, the PCI standards are vague enough that the card brands can probably find enough cause to determine that Hannaford Bros. was, in fact, noncompliant at the time of the breach.