The online study of 1,000 Americans of varying ages, genders, incomes, and locations indicates that just over half of consumers aren't interested in a mobile-wallet payment system. Another 26 percent say they don't know what "NFC" or "mobile wallet" means. And just one in five people want to pay for items with their phone.

Despite Google's leadership role in the mobile payments, Apple iPhone users appear more enthusiastic about NFC technology. Forty percent of iPhone owners say they want to make payments with their next cell phone, versus only 24 percent of Android owners, according to study.

The iPhone 4 isn't NFC-capable, and it's unclear whether the next-generation iPhone, rumored to debut in the fall, .

It's likely that US consumers will warm up to mobile wallet systems as the technology grows more mainstream. As Retrevo points out, however, NFC proponents have to do a better job of addressing consumers' concerns about security.

When will Americans warm to NFC? When they start spotting early-adopter friends, colleagues, and random strangers paying for things with a simple swipe or tap of a phone.