Steam has been 'pwned'. Security is everybody's business. Be smart.
A hacker, or hackers unknown have broken through security measures at Valve, defaced the Forums, and obtained a copy of a Steam database that lists encrypted credit cards, as well as usernames, and hashed/salted passwords. Okay this is bad.
But I bet you Gabe is thanking his lucky stars that they didn't choose to store Steam user passwords in plaintext in their database. Let this be a warning to anybody else out there; Don't ever store anything important plaintext in your database. Ever.