According to Isis, 25 of the nation's top 100 retailers already have contactless terminals that will process NFC payments in at least some locations.

Experts in the mobile payments space did not share Isis' optimism about its future acceptance when it rolls out nationally.

Drew Sievers, CEO of mFoundry, wrote in an email: “There are certainly more merchants [now] with NFC, but it's still statistically small relative to the merchant universe. While there are 20 million phones with NFC according to the Isis release, that's still only a bit over 5% penetration, and that doesn't mean that 20 million people are using, or even understanding, NFC.”

He added: “NFC will grow next year for certain, but I'd be surprised if it was anything but a rounding error in the world of payments.”

Bill Clerico, a founder of payments innovator WePay, said in an interview that he is “a bear about Isis. I don't see what's in it for the consumer to want to use it.”

He added, “The plastic card in my wallet works every time.”

Clerico acknowledged that on paper a tap-and-go smartphone payments tool is cool but so what? “Silicon Valley is filled with companies with cool tools and no market. Consumers have to want to use what you are offering and I don't see that with Isis and NFC,” he said.

A common concern around NFC payments on smartphones – beyond the paucity of NFC equipped devices and a similar lack of merchant readiness – is that the Isis carriers apparently want a slice of the already small payments pie.

That money has to come out of somebody's pocket and, so far, there has been no rush to offer to take lesser cuts by merchants, credit card issuers or financial institutions.