Philip Reitinger posted a letter on several SOE forums informing players that their accounts may have been compromised.
The good news is that less than 0.1% of Sony's entire playerbase has been affected. The bad news is that that leaves around 33,000 SOE players -- in addition to Sony Entertainment Network and PlayStation Network customers -- whose accounts were hacked. Following the intrusion, Sony temporarily locked the accounts and is investigating the situation.
"Only a small fraction of these 93,000 accounts showed additional activity prior to being locked," Reitinger said. He assured customers that credit card numbers were not leaked and that any purchases made during this intrusion will be restored. SOE customers with locked accounts will receive an email with instructions on how to validate their credentials and restore their service.