That vision of paying for goods and services with your phone anywhere you go? You shouldn't hold your breath.

While there are trials and select deployments of payment terminals and cash registers that can accept mobile payments, the method won't hit the mainstream in the U.S. for another two to three years, according to Bill Gajda, head of mobile for Visa.

"We're seeing momentum in 2013," Gajda said in an interview with CNET. "But it's really about commercial launches and scale."

Visa has been one of the bigger companies spearheading the idea of mobile payments -- where consumers can tap their phone in front of the cash register or payment terminal to pay for groceries, a taxi ride, or other things.

Visa is using the Olympics as an international showcase for mobile payments. The company has hooked up 140,000 payment terminals in London with near-field communication, or NFC, chips that enable the tap-and-pay process.