If you keep secure passwords, different for every site, and have various anti-spyware apps installed and up to date, you really don't need to worry about this happening to you. OP got phished, or perhaps he uses the same pw everywhere and it got out in the wild.
There's no reason for all the hoopla fear about having your CC details on PSN if you have your shit together.
This seems to happen much more with Sony than other big name services. I've heard their security in general is pretty out of date, wonder if that's true.
This has nothing to do with Sony's security. They weren't hacked or breached. Any security lapse was on the OP's side.
Sony's security is more up to date than most companies, given they completely overhauled it after the breach a few years ago (that wasn't even that bad, though got tons of press because they took PSN down while they fixed/investigated).
Most issues occur due to:
Unsecure info on your personal computer (key loggers, spyware, etc).
Reuse of passwords (some other site gets your pw, now it is tested everywhere else)
CC details got loose via other means (can happen anywhere, for example, at a gas station, etc)
There's an entire industry of stolen credit cards. Getting, testing, using. If your card is in the wild, and used at store ABC, often store ABC has absolutely nothing to do with it. They're just where the CC was used.
Wh .. what?
3) All major credit cards do *actual chargebacks* where the money is taken away from the card processor, you have to fill in a bit of paperwork but it's pretty easy. (This by the way is how you can force Paypal to refund you instead of working through their "well, we'll try to get your money back" dispute process.)
Chargebacks are extremely expensive for the company being charged back (in this case, Sony). They are often responsible for both the amount itself, plus a fine.
For example, I send you a Gadget for $10, and you charge me back, I'll likely be out the Gadget itself, have to pay back the $10, and get fined on top of it. For this reason, it's extremely common for companies to ban customers for chargebacks, because people use chargebacks to -commit- fraud all the time, not just protect themselves from fraud. For example, if they want to get that Gadget for free, or they have buyer's remorse and don't want to spend the money anymore, or if their kids bought it.
Chargebacks should be used as a last resort -only-, for example if a company charges you $100 instead of $10, then doesn't answer your emails for a couple weeks.
In the case of PSN digital goods, the chargebacks can still add up to be very expensive for Sony. Even a relatively small company can easily be paying tens of thousands of dollars in chargeback fines, depending on what exactly they're selling... I can imagine Sony's chargebacks top that simply due to size.
(my avatar is from the box art of Leisure Suit Larry 5 though, but i like that artwork of Passionate Patti better compared to the LSL3 box art).
