Some close friends (in Japan) got contacted by Sony who put in place a Call Center regarding the recent PSN Hack. These friends called the Call Center, and where advised to call their bank and cancel their credit card. When asked, the bank agreed that this was a wise move.
Although Sony didn’t officially admit that credit card numbers have been stolen during this intrusion, this is probably a security measure from them. Better safe than Sony (huhu) as they say. So unless you have very very good reasons to not cancel your credit card, this might be a wise move.
What’s even more confusing is that I personally didn’t get any email, although I have 2 different email addresses and credit cards registered on their website… Are Sony sending this only to a few users whose account got compromised, or just sending the emails progressively? Is google’s spam filter playing tricks on me?