Bill from Hyatt E-Commerce here.

To "Somewhere over the atlantic" and others concerned about credit card security, I wanted to let you know that that credit cards are strongly encrypted and our web systems are all fully PCI compliant and always have been. Security for the web site is reviewed by our internal security team as well as a third party. Given the additional sensitivity surrounding storing credit card numbers on the web site, we conducted an additional review by a second third party to ensure there would be no issues.