I dont think any programming group has admitted to the hack, one of the reasons why Sony is still invetigating the matter. It must have been a serious breach for them to take the network down for so long.
If you stored any card details on your PSN network I would be aware. You have to think just how many card details there are in the network, not just the UK but globally.
Personal details I would not worry about as people can obtain that data not just from the PSN network
The chances of your card details being used are very slim so I doubt its anything to worry about.
Sony are in the shit though thats for sure, depending on the security breach it could take them a lot of time to sort the coding out and implement new security measures. I feel sorry for the poor Sony coder's, they must have a diet of Red Bull and pizza at the moment
Still, the PSN is a free network so you can't moan to much and like anythiung of this nature your always in danger of something like this on other online systems, some don't even get taken offline like Sony has the PSN.
Anyway, as for who did it?
Bill gates has been a bit quiet recently don't you think? His Xbox Live! susb must be going through the roof right now! Good hack by him if he did it