The long-awaited debut of Google Wallet was finally announced today, marking a watershed moment for mobile payments. But there is much more to expect, when it comes to the mobile world.

Thursday midday in New York, Google finally announced today its NFC-based contact-free payment system Google Wallet and Google Offers.

The way it works is quite simple. With an NFC-enabled smartphone, you could simply wave your phone in front of a sensor, to have your purchase placed onto your credit or debit card right away.

With this tap and pay method of purchase, your phone will literally replace your wallet.

As Google taps into mobile payments service, Google is expecting four-fold growth from the initial stage, to have 150 million smartphones to be NFC-enabled by 2014.

Google Wallet will begin today with a full launch expected this summer. Initially available on Nexus S 4G on Sprint smartphones.

More than 300,000 merchant locations in the United States will be adopting Google Wallet in their payments system.

Google's Commerce VP Stephanie Tilenius said that Google wanted to create tomorrow's best shopping experience and bring online and offline together through an open payments platform.

While Google Wallet's debut is a significant, watershed moment for digital money/electronic payments, Google is not the first player in the global market.

Japan has already set the precedent for mobile payment, with 60% of mobile phones in use are equipped with mobile payment technology, and 15% of mobile subscribers actually use mobile payment. Following Japan, South Korea and Europe have also well adopted mobile payment, and stay ahead of the U.S.

In Japan, the usage of mobile phones has been developed extensively, including mobile payments, subway cards, retail membership cards, concert tickets, coupons, airplane tickets, and much more.

Don't be too puffed up by Google Wallet - this is just the tip of an iceberg.

The evolution of Google's NFC-enabled phones will also far surpass commerce, hopefully soon, to catch up with Japan and Korea. The smartphones will also allow you to check in with sensors around a city to instantly load information onto your device.

NFC-enabled smartphones will potentially function as hotel keys, which can allow guests to check in and use their mobile phones as room keys even before entering the building.

NFC technology will also be equipped on other smartphone companies as well. Nokia has stated its plan to have NFC-enabled Symbian phones by next year, and Apple is rumored to be quietly developing an iPhone-based NFC.

AT&T, Verizon Wireless, and T-Mobile is forming a joint mobile commerce network structured around NFC technology called Isis to be launched in 2012.

As Google Wallet replaces your wallet, be ready for the furthur evolution in the mobile world.

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