Visa, in particular, is pushing hard in the mobile payment space here at CTIA with a large booth presence. The company is showing of its payWave NFC payment system, V.me, and Visa Mobile Prepay — all of which are solutions that go beyond what ISIS provides and, frankly, would obviate the need for ISIS were they to win out in the marketplace.

We spoke with Brad Greene, head of strategic business development for the mobile commerce unit of Visa, about the company's strategy. When it comes to ISIS, Greene tells us that Visa has licensed payWave to the joint venture so an ISIS wallet can communicate with Visa's systems. However, Visa believes that "ISIS is focused primarily on the NFC space," while Visa is focused on "the user's information stored in the cloud [and] being able to transact remotely." Even so, Visa isn't ceding NFC payments to ISIS entirely, it will continue to offer its own payment and wallet solutions.

Ed McLaughlin, Mastercard's Chief Emerging Payments Officer, takes a slightly more friendly stance towards ISIS, "I wouldn't characterize ISIS as a competitor." However, like Visa, Mastercard is not throwing in with the joint venture entirely, preferring to hedge its bets with its own system and keeping ISIS at arm's length. "Hypothetically if ISIS came to us and said we would like to hook our wallets into your network, we would consider that — just like we would consider any partner who came to us."

So while it's possible that ISIS could become a universal standard, it's very far from a sure thing. Yes, it has the backing of three of the four major US carriers, but the biggest credit card companies will offer their own competing wallets and networks. Both Visa and Mastercard (and, presumably, many others) will allow their banking systems to be plugged into ISIS's wallet, but at the same time they are making that case that consumers will want to use their systems instead.

Visa, in particular, was clear that ISIS may have a place in mobile wallets, but it didn't want carriers inserting themselves anywhere else in the payment stack. Greene pointed out that he thought carriers made for a great "retail distribution network" and could serve to education consumers on mobile payments, but that ISIS and NFC are little more than "technology enablers."