According to Gabe Newell and Gamesradar it was:
http://www.gamesradar.com/steam-hack-confirmed-encrypted-passwordscredit-card-information-stolen/
Personally I'm not too worried and yet there is still some mistrust left over from the PSN hack, hopefully more information will come to light soon.
http://www.gamesradar.com/steam-hack-confirmed-encrypted-passwordscredit-card-information-stolen/
Personally I'm not too worried and yet there is still some mistrust left over from the PSN hack, hopefully more information will come to light soon.