The new system for publishers and marketers will be integrated into ValueClick's existing ad-serving platform and will include a variety of formats, such as video, rich media and standard display ads.

ValueClick estimates that one-quarter of the publishers in its 13,500-site network already offer video, and projects that half will offer it by the first quarter of next year. Inventory of about 100 million video streams will be available at launch.

With the move, ValueClick also takes direct aim at Advertising.com, the Web's largest ad network. Earlier this year, it acquired online video ad company Lightningcast to boost its own video-ad serving ability. Advertising.com sites reached 84% of the U.S. Internet audience in October, while ValueClick's reach totaled 77%, according to comScore Media Metrix.

"A lot of our competitors got into the video ad space by acquiring other companies," says John Ellis, vice president, product management at ValueClick Media, the ValueClick unit that operates the ad network. "We've integrated video into our existing platform so that on Day 1, advertisers can take full advantage of this."

Helping to fuel investments in video ad technology is recent research showing that video is the fastest-growing type of online advertising. Market research firm eMarketer predicts that Internet video advertising will be a $3 billion business by 2010, compared to a $410 million one this year.

This emerging market has also given rise to a crop of nascent video ad networks, such as Tremor Media and BrightRoll, seeking to compete with established online ad networks.

Ellis says ValueClick considered buying video ad expertise before building its own system, but found that smaller companies wouldn't be able to serve video ads on a large ad network. "They weren't accustomed to dealing with the scale that we are."

For advertisers, ValueClick its touting the reach of its network as a way to go beyond the top Internet properties to unlock the "long tail" value of Web video content.

Publishers, meanwhile, would be able to easily add video to existing account management tools and take advantage of the higher CPMs commanded by video ads.

ValueClick is also planning to syndicate licensed video content to publishers to help generate video ad sales. ValueClick network publishers include Guardian Unlimited, InsideHoops.com, Jobs.net and The Harvard Business Review.

Recently, ad technology companies DoubleClick and Atlas, a unit of aQuantive, introduced their own video-ad serving systems for advertisers and publishers. Ellis said ValueClick clients would still be able to use third-party video ad-serving software from those companies or others if they chose not to use ValueClick's new video ad system.

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