While the upgrades represent a major step forward in usability for Google Wallet, they may not be enough to spur widespread adoption in the U.S. NFC payment is still not accepted by most American retailers, and the technology faces an thanks to a general lack of awareness and security concerns, valid or otherwise.

Nevertheless, rumors that the 5 will could help drive customer demand, pushing the technology into the mainstream.

UPDATE: American Express has since stated publicly that, although negotiations are ongoing, it does not yet officially support Google Wallet. Users can link their Amex cards to the system for the moment, but reports indicate that the credit card issuer can turn that functionality off at will.

Email Jon Gold at jgold@nww.com and follow him on Twitter at @NWWJonGold.

in Network World's Software section.