Chris LaSala, head of agencies at Google, would not disclose details of the new phase, but said it was the outgrowth of a meeting held in October by a new council of industry thought leaders from Google's top ad agencies. "They accepted it as a concept, and their feedback is helping us develop beta version two," LaSala said.

The agency council is a more formal version of a series of periodic meetings that Google has been holding with leading ad agencies in its Mountain View and New York offices.

"We get them in our offices and ask them, 'What do you think?'" LaSala explained. He said both magazine publishers and advertisers involved in the test have been happy with the results to date, which have involved print buys in magazines such as PC, Maximum PC, and Budget Living.

While LaSala declined to elaborate on the next phase, Google spokesman Michael Mayzel confirmed that Google is exploring other ways of extending its reach via other forms of offline media.

"We're not going to provide any particular product plans, but we are always looking at new ways to extend our reach--and that could include other forms of media," he said, although he would not say whether that would necessarily be part of phase two of the media buying beta test.

Meanwhile, many online marketers have yet to embrace the opportunity to advertise in magazines and newspapers. "For the most part, our clients have not been interested in participating," said Joshua Stylman, a managing partner at search engine marketing firm Reprise Media.

One of the largest stumbling blocks, he said, is that it's not as easy to assess return on investment from print ads as it is from pay-per-click search links. "There are absolutely some inherent challenges when you look at media across different platforms," he said. "How do you measure it? And how do you get comparisons from one to another?" Stylman asked.

He added that clients of less niche agencies--those with a background in both traditional and online advertising--might be likelier candidates for the new service.

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