New group-buying company Offermatic introduced an expanded automatic rebate platform today as it seeks to distinguish itself in what is rapidly becoming a crowded playing field for online shopping.

The company, which came out of stealth mode last month, bills itself as a “Groupon/Mint.com/Blippy hybrid” that doesn’t share user information publicly.

Groupon and other group-buying competitors sign members up to receive deeply discounted offers from local merchants looking to grab new customers and hip reputations online. Mint.com, acquired last year by Intuit, helps users track their finances online, while Blippy allows users to show recent credit-card purchases to friends.

But Offermatic says it uses a new model that improves conversion rates of return customers by 10 to 100 times over existing methods for merchants by linking “virtual coupons” directly to consumers’ credit cards.

The announcements it made today include:

* Partnerships with 150 merchants — that’s up 100 percent from 75 merchants at its launch Dec. 7.

* Members can now get more valuable offers by progressing through different “levels” within the Offermatic platform, unlocking better offers by using their points.

* Members earn points for adding more debit or credit cards to Offermatic, for transactions made using those cards, for inviting others to use Offermatic, and by sharing offers on Twitter and Facebook.

Offermatic enables online targeting of offline purchases – where 94 percent of all commerce happens – bringing the hyper-targeting of Google Adwords to real world commerce.

The company said its new tools will keep it competitive in the increasingly crowded group-buying space as it tries to tempt new members into using technology that makes redeeming offers easier.

“We introduced some elements of game mechanics to the platform that give members the opportunity to use their points to level up to even higher savings levels,” Faisal Qureshi, founder and CEO of Offermatic told me. “With our expanded platform, better deals, and new merchants, Offermatic becomes significantly more competitive.”

The company is currently funded by private angel investors, with seed funding by Kleiner Perkins Caufield & Byers and Bessemer Venture Partners.