Google has updated a patent application that has to do with a new form pay per action advertising that would work well with Google Voice. Google Voice is getting easier to use and more popular with the introduction of new apps for Android devices and Blackberry phones.

The updated patent application was filed last year on what Google calls ringback advertising. Ringback advertising is a form of audio advertising that plays an ad while the phone rings rather than the ringing we are all familiar with at this time.

Several mobile service providers already offer ringback tones, so the idea of replacing the plain ring with other content isn’t new. InformationWeek reports that the patent application says that audio ads would annoy consumers, but audio ads when the phone is ringing would not.

Google says this type of advertising wouldn't annoy, "Because the consumer would have to otherwise listen to some other form of audio." The audio ads would run while the calls between services like Google Voice and the other party was being connected. The patent application doesn't specifically mention Google Voice, but when the patent app was filed, Google Voice wasn't around.

Google has acknowledged that it is looking for ways to monetize Google Voice. Google has coined a couple new terms to go with the new program called cost-per-call and listen-through. In the lucrative online ad market advertisers are charge on a cost-per-click scheme and a click-through when the party clicks the ad and goes to the advertiser's site. The cost-per-call is similar to the cost-per-click and the listen-through will be when the called hears all or part of a message.

The patent application says, "A listen-through can occur, for example, when a user of a user device, listens to some or all of an audio advertisement provided by the advertising management system."

InformationWeek reports that there is another patent application from 2007 that appears to cover the same concepts of ringback advertising. Whether or not the two patent applications overlap will be up to the U.S. Patent office to decide.