Mobile Payments will be HUGE in the near future.

It was revealed Monday that Google has acquired Zetawire, a small stealth startup focusing on mobile payments.

Zetawire was in an extremely early stage when snapped up by the tech giant; we know little about what it was working on…

However, an analyst with 451 Group revealed the startup had been granted a patent for “mobile banking, advertising, identity management, credit card and mobile coupon transaction processing” — in other words, all the puzzle pieces needed to let users treat their smartphones like a credit card.

Interestingly, this deal wasn’t closed in the recent past; the acquisition was concluded back in August, around the time Google also bought up social apps startup Slide (which was led by a Paypal co-founder) and social currency company Jambool.

Zetawire’s technology might mesh nicely with what Google has been doing in the area of NFC (near-field communications). The company has been testing NFC-related tech as part of a soon-to-be-national location-based ad campaign for local businesses. And the Nexus S, Google’s successor to the Android-powered Nexus One, comes with NFC hardware already in place.

The startup’s co-founders were Alex Hertel, a Toronto-based theoretical computer science researcher, and his brother, Philipp.