Here is the latest official information from Google on their payments capabilities. They will use the Google Account as the base for your information.

Official Google Blog: An update on payments

As the number of Google services has increased, we’ve continued to build on our core payment features and migrate to a standard process for people to buy our services with a Google Account. Examples of this migration include enabling users to buy Google Video content, Google Earth licenses, and Google Store items with their Google Accounts. We also just began offering similar functionality on Google Base.