To be honest the credit card details aren't the worst part of it. Sure it sucks but what will happen for most people is that they'll cancel their cards and get new ones so those details won't be useful for very long. Even if they do get used to make some purchases, most banks have fairly strong anti-fraud policies so the impact to you is likely to be quite small - a bit of inconvenience but probably no financial hit.
What is worse is that a lot of your identifying info including your email address, physical address, telephone number and PSN password has been compromised. A lot of people are dumb and use the same passowrd (or simple variants of it) everywhere so I'd expect given a sample the size of the entire PSN customerbase to have a lot of not very security minded people. Why steal your credit card details when they can log into your email, get your bank details and order a new one that you don't even know about? Or apply for a loan? Or go to your Amazon account and buy lots of random stuff using your saved payment details?
If you used your PSN password anywhere else, you should be going around and changing it everywhere you can even if you never bought anything on there before.