On Wednesday Google said that it will team up with Nielsen in order to bring demographic data to the Google TV Ads advertising platform. By combining Nielsen demographic data with aggregated set-top box data, Google can provide advertisers and agencies with comprehensive information to help them create better ads for viewers and maximize the return on their advertising spending.

This partnership is an effort to know exactly how many people are actually watching the ads. Advertisers can better understand exactly how their ad is performing and make near real time changes to their TV advertising campaigns to deliver better ads to viewers.

The reports about specific ads will be available through Google AdWords report center 24 hours after they were released.

Google TV ads are bought using an auction model and through a single online interface that is already familiar to agencies and advertisers. Advertisers can target by demographic, daypart and channel and pay only for actual impressions delivered. Pricing is on a CPM basis.

“This is an important, strategic relationship for both companies and a great fit,” said David Calhoun, Chairman and CEO of The Nielsen Company. “We are pleased that Google looked to Nielsen to provide the demographic data that is so critical to the clients of its TV advertising platform. The relationship with Google – which we expect will expand significantly in the months ahead – is a prime example of the ways Nielsen is embracing new technologies, platforms and relationships worldwide to serve clients more completely, to provide companies with its insights and to help expand the base of potential advertisers everywhere”

Google TV Ads has started as a trial this summer and Gooogle’s partner is EchoStar's Dish Direct broadcast satellite service and Astound Cable. EchoStar has around 13 million Dish subscribers and among the advertisers who already subscribed to Google TV Ads are names like Intel Corp., E*Trade Financial Corp. and 1800Flowers.com.

“We are going to build an ad network for television and it’s going to work,” Michael Steib, director of Google TV Ads. “In the TV space we can be a real asset in augmenting the usual sales process. All the things that happen today, like sales guys getting together and coming up with integrated packages, doesn’t go away and it doesn’t get automated, but then there is this slice of activity in the TV space that we can help.”

Earlier this month Google unveiled Video Units, a platform which enables publishers to display relevant, targeted video content within a customized, embedded player that’s ad-supported. The videos are delivered via YouTube and for the moment.