Google Voice to add Audio Ads?

0 reports that according to Unwired View, Google Voice just filed an application with Fish and Richardson legal services on a patent that is suspected to monetize caller waiting on Google Voice.

The patent application lays claim to the methods and software “in which an indication of a telephone call being placed from a calling number is received, and a determination is made of an audio advertisement to play based on the calling number.”

An ad serving engine will store audio ad files and play them when a caller would normally hear a ring tone, call waiting tone, or hold tone. The patent covers the method of determining a callers location and serving up ads based on locational info. Depending on where you’re from, where you’d normally hear a regular ringtone, you might hear everything from the hottest electronics to the hottest sport fishing equipment.

Essentially this looks like an expansion of the pre-existing Audio AdWords. While Google closed down its broadcast radio ad program in February, the company continues to work with advertisers on online streaming audio and radio sites. Basically Google already has a slew of pre-produced audio ads sitting in its ad serving engine. Depending on the fit of the advertiser, it may be a no-brainer for companies to throw Google Voice into their mix of marketing efforts.

If this project takes shape, the really interesting part will come a month later when advertisers are billed. With streaming audio ads, companies get a relative amount of assurance that the audience is listening to the entire ad, including the call-to-action. While audience members can always mute advertising or pull out their headphones, a site’s main audio content often will not play without the obligatory intro ad.