Forbes has a good article describing Apple’s new payment system designed to allow users to load multiple credit cards on their iPhone 6 or 6 Plus.
Apple Pay is really two ways to pay rolled into one. The most visible of those will be using your iPhone to pay in retail stores, verifying your ID with the fingerprint sensor. That version of Apple Pay will replace the traditional credit-card swipe.
It will be interesting to see this play out in the marketplace. There seems to be plenty of ideas on how to simplify the use of credit cards for payments. I’m for any solution that makes the buying experience simpler for the customer.