Google on Monday debuted its long awaited Google Wallet that is intended to free users from the need to carry plastic credit cards.

Eventually.

Right now, what Google has in fact debuted is a smart phone app that runs only on the Google S 4G Android phone on Sprint, only in the United States.

At launch, use of the device also necessitates having a prepaid Google card or an existing PayPass-enabled CitiBank Mastercard. Google said that around 300,000 merchant locations will accept “tap and go” payments from the phone.

Google is using Near Field Communication to transmit data from the phone to the merchant, making this probably the biggest rollout of NFC in the U.S.

Nonetheless, observers referred to this Google Wallet debut as “a baby step,” mainly because of the small number of merchants and, frankly, no expert anticipates a stampede of new subscribers to Sprint, a distant third in the mobile carrier races.

Nonetheless, experts also are persuaded that Google Wallet is a loud first salvo in the war to put most of our financial information inside a cellphone. That makes this a must follow for credit unions, suggested the experts.

Google had first introduced its Wallet in May amidst much media hoopla but until now its use had been limited to a small pilot group. The Sprint launch opens it up to any user.

Almost immediately after launch Google announced it had licenses to add cards from American Express, Discover and Visa into its Wallet. It did not indicate a timeframe.