A press release posted on Daily Kos, by Barret Brown, who claims extensive contacts with the collective, says, "Anonymous as never been known to have engaged in credit card theft." The release also says that the perpetrator could have left a 'calling card' to frame the group's members.
Sony was hit with a massive cyber attack on April 19, which resulted in the theft of details for nearly 100 million users of the PlayStation Network and Sony Entertainment Online. Credit card details for millions of users were also taken. Sony has said that the attack displayed a high level of sophistication, and that it came right on the heels of a distributed denial of service attack that took Sony's PlayStation Network offline for a few hours.
Link to Original Source