Google Wallet has launched on time in New York and San Francisco, letting consumers pay via short-range NFC technology on Sprint's Samsung Nexus S 4G Android smartphone. In a surprising turn, Visa, American Express, and Discover have joined Citi and MasterCard as credit card partners in the venture.

Google met its self-imposed goal to launch its mobile payment service this summer, as Google Wallet rolled out Sept. 19. Consumers in New York and San Francisco can now pay retailers with their Android phones.

The launch came with a surprise bonus: Visa, American Express and Discover have joined Citi and MasterCard as credit card partners.

Unveiled in May, Google Wallet includes a mobile application that communicates with smartphones equipped with near field communication (NFC), a short distance wireless technology. At the moment, the only relevant device is the Samsung Nexus S 4G (pictured), available from Sprint.

Nexus S 4G phone owners will receive access to the Wallet through an over-the-air update. Once they receive the app, Nexus S 4G owners can tap their phones against an NFC-enabled cash register to pay for goods at some 20 retailers and restaurants.

Google Wallet will initially support Citi MasterCard and a Google Prepaid Card, which can be funded with existing plastic credit cards and used at any of the 300,000 stores worldwide that accept MasterCard PayPass. Google is offering a $10 bonus credit to users who set up the Google Prepaid Card in Google Wallet before the end of 2011, says the company.

Visa, American Express, and Discover have also pledged to enable their cards to support the service in the future, Osama Bedier, Google's vice president of payments, announced in a Sept. 19 blog post. Visa has previously stated that Google has licensed its payWave contactless payment software — Visa's answer to MasterCard PayPass. The newly announced deal will enable Visa account holders to make purchases using Wallet.

"Our goal is to make it possible for you to add all of your payment cards to Google Wallet, so you can say goodbye to even the biggest traditional wallets," Bedier wrote, adding that the Wallet would be available on more phones in the future.

Early reviews promising

Some early reviews of Wallet appeared Sept. 19. On ThisIsMyNext, Chris Ziegler writes that the service works well, but is still incomplete. GigaOm's Ryan Kim found more glitches, but seems to like the service even more, calling it "cool and futuristic" and "a good platform to build upon."

Wallet stands at the vanguard of a number of emerging mobile payments solutions, including those from Square and PayPal, as well as Isis, the mobile payment triumvirate formed by AT&T, Verizon Wireless, and T-Mobile. Isis won't launch until 2012, but it will do so with support from all of the major credit card providers.

With its newly announced partners, however, Google Wallet will be able to match that line-up. It's currently working only with Sprint as a carrier, however, and as noted earlier, there are only about 20 Google Wallet retail partners, including Macy's, CVS, and American Eagle.

One of the challenges Wallet and all of its rivals will have is selling the consumer on the notion of mobile payments via smartphones. There is no proof that consumers will embrace such technology after shoppers have spent the last several decades using plastic cards they simply swipe at checkout.

Moreover, although Google developed its latest Android 2.3 ("Gingerbread") operating system to support NFC technology, the Nexus S 4G is currently the only phone equipped with a special NFC chip to securely store users' credit card data.

Google may have the advantage of an incentive with Google Offers, the company's Groupon clone service that entices consumers with discounts of 50 percent off or more for goods and services. Offers is live in three dozen cities around the country, including in San Francisco and New York, where Wallet is now available.

Deal aggregator Yipit claims Offers has suffered declines versus rivals Groupon and LivingSocial of late. However, a Google spokesperson said the company is pleased with Offers so far.

Clint Boulton is a writer for eWEEK.

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