PlayStation Network credit cards protected by encryption

All credit card information stored on Sony’s PlayStation Network was encrypted, the company said 1 day after warning users their user names, passwords, birth dates, and home addresses were stolen in a security breach.

“The entire credit card table was encrypted and we have no evidence that credit card data was taken,” Sony representatives wrote in the update, which was posted late April 27. “The personal data table, which is a separate data set, was not encrypted, but was, of course, behind a very sophisticated security system that was breached in a malicious attack.” The update clarifies statements Sony made April 26 that the stolen information may have included payment-card data, purchase history, billing addresses, and security answers used to change passwords. The company did not provide details about the encryption used to protect card data, but assuming it followed standard industry practices, it was likely enough to prevent the information from being used by the hackers behind the break in. The update April 27 follows multiple news reports that recounted PSN users who reported credit card fraud that seemed to coincide with the breach.
Source: http://www.theregister.co.uk/2011/04/28/sony_playstation_network_credit_cards/