Steam forums were hacked earlier this week. While steam says the forums are separate from the account, if you do use steam, change your password and watch any credit cards you had on file with them.
Thankfully Ive never registered for the forums but I still changed my steam password.
as a follow up I'd just like to say...I hate Steam and all companies that force you to use their service. That is all.
At least Gabe is up front and honest about it. Better service than you'd get from most banks, and they aren't likely to keep your information encrypted on their back-end systems.
http://store.steampowered.com/news/6761/ (http://store.steampowered.com/news/6761/)