Apple's Cook says Apple Pay already huge hit

Apple CEO Tim Cook says more than 1 million people have already activated their credit cards with his new mobile payments systems, Apple Pay, making it a massive hit.

"We've been told by MasterCard and Visa that if you summed up everyone else in mobile payments, we're already No. 1," said Cook at the WSJDLive conference here." We're more than the total of all the other guys, and we've only been at it for a week."

Apple Pay was launched last Monday in the U.S. to a handful of stores with 220,000 locations, including CVS/RiteAid competitor Walgreens, McDonald's, Subway, Panera Bread, Macy's and Bloomingdales.

While the number sounds impressive, it's just a sliver of the total retail pie, excluding such huge big box retailers as Wal-Mart, Sears, K Mart and Target — although Target works with Apple Pay via its mobile app, but not at retail locations.

Yet over the weekend, retailers CVS and Rite Aid, which hadn't initially signed up with Apple Pay, disabled its mobile payments retail pinpads, when it was discovered that customers were using them for Apple Pay instead of Google Wallet, as had been initially intended.