Right around MW3, Skyrim, and Sonic Generations. Who ever did it played smart.
This week Valve Corporation head Gabe Newell has announced that the gaming hub Steam has suffered an attack on their forums which may well have put credit card numbers and other users personal information at risk. The attack apparently went down this Sunday and Valve is currently letting everyone who had any personal info listed at Steam to watch their credit card activity in the near future for possible fraudulent activity. Here after the attack the Steam Forums are closed and will remain closed for the time being while Steam itself will remain operating as normal.
Note that the attack itself was not necessarily aimed at the credit card information and other personal bits of users at Steam, but that the larger attack did have the potential to access said information. A note from Newell read something to the effect of don’t be scared, but also keep your guard..... (more on link)