Google is joining the race to dominate the mobile payment market in partnership with MasterCard, Citibank, Spring and various retailers. The company will announce a "mobile wallet" service available that will enable users to make payments on MasterCard PayPass terminals. The Atlantic Wire's Adam Clark Estes anticipates the reactions from Google's competitors:

Obviously, Apple is going to be upset by the announcement that Google will beat them to market. Bloomberg reported in January that Steve Jobs and his crew had been working on integrating N.F.C. technology into the iPhone and iPad in an effort to grab a share of $6.2 trillion American consumers spend every year. The company hired a mobile payment guru and applied for a patent on N.F.C. technology for Apple apps to communicate with each other but have yet to announce a plan. The Apple fan blog, Cult of Mac, speculates this morning that Apple's mobile wallet is unlikely to be unveiled before 2012. 

It's entirely possible, however, that Apple is being characteristically Machiavellian in its mobile payment strategy. N.F.C capabilities top the list of rumors swirling about the release date and feature set on the iPhone 5, and the June deadline for the annual iPhone update is just days away. Apple could presumably drop a bombshell at the Worldwide Developers Conference beginning June 6. An N.F.C.-enabled iPhone that depended on mobile payment start-ups to figure out the details would immediately stand to grab a larger market share than Google's still relatively restrictive program which demands users use the still not super popular Nexus S.