"This is another game-changer on the part of Google," marveled Marc Rosenstock, I-Media Business Transformation Leader at Procter & Gamble.

DoubleClick presently sells software that allows Web publishers--in many cases, Google rivals like AOL and News Corp.--to display ads on their Web sites.

A major question raised by Google's move, Rosenstock added, is whether these publishers will now take their business to a DoubleClick rival. "It will be interesting to see whether DoubleClick's publishers stay, or take their business elsewhere," he said.

DoubleClick's main competitors include aQuantive and 24/7 Real Media.

Many in the industry were expecting Google to develop its own ad-serving tool to compete with the likes of DoubleClick.

"I guess Google has the money, but I didn't think they'd have to go to another company for this technology," said Marjorie Lau, vice president of marketing, North America, for Estée Lauder.

An optimistic Andrew Ianni, chairman of programming at ad:tech North America and former Jupiter Research analyst, said the deal will clearly help Google accelerate its display ad business and foster relationships with Madison Ave.

"They're buying relationships with the advertiser community," said Ianni. "Some very strong relationships."

The benefit for DoubleClick, Ianni added, is clear: "This means a far greater return on investment for their investors," he said.

A less optimistic T.S. Kelly, senior vice president and director of research and insight for Havas' Media Contacts, did not see the acquisition as a simple matter of buying relationships.

"We've always had good relationships with DoubleClick," said Kelly. "But in general, Google has not always had the best relationship with agencies. They have a history of not engaging with us, so it remains to be seen whether this will change things."

Some see Google's plans to buy DoubleClick itself as an olive branch to Madison Ave. "This seems to be Google expressing its desire to improve its relationships with marketers," said Taddy Hall, chief strategy officer at the ARF, a nonprofit group that studies advertising.

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