Back in November, we told you about a joint venture between AT&T and Verizon Wireless (it also includes T-Mobile, which AT&T is trying to acquire) on a mobile payments network. The offering, called Isis, allows users to pay for purchases from their smartphones.

Now, Isis is getting a new injection of funds to the tune of $100 million from the three mobile carriers, as it aims to take on Google Wallet, according to a report from Bloomberg.

“Our mobile commerce network, through relationships with merchants, will provide an enhanced, more convenient, more personalized shopping experience for consumers,” Isis CEO Michael Abbott said back when it was announced.

“While mobile payments will be at the core of our offering, it is only the start,” he said at the time. “We plan to create a mobile wallet that ultimately eliminates the need for consumers to carry cash, credit and debit cards, reward cards, coupons, tickets and transit passes.”

Google introduced Google Wallet in May as an app that turns your phone into your wallet:

“A key benefit to retailers will be the integration of coupons, or offers, into Google Wallet. We’ve been testing a variety of offers – from discounts directly within search ads to check-in offers to offers in Google Places,” said Google Director of Commerce Partnerships, Spencer Spinnell. “Over time, consumers will be able to save each of these offers directly to their Google Wallet. That means consumers will get the benefit of carrying their offers with them at all times, bringing retailers targeted foot traffic.”

With Google trying to acquire Motorola Mobility, it will be quite interesting to see how all of this plays out. Remember that Google Wallet will likely be integrated with Google Offers and Google+.