Advertisers also get site-by-site performance metrics with the reports--from clicks and conversions to domain and cost data--information that will enable them to fully optimize their contextual advertising campaigns.

Agency insiders say the reports are a big step toward being able to deliver the budget accountability clients look for with digital campaigns. "One of the challenges with contextual advertising has been the inability to view which specific sites were performing well," said Sean Muzzy, senior partner, group planning director, Neo@Ogilvy. "That ambiguity was difficult to explain, especially to marketers who were more familiar with traditional channels."

While Google has offered options such as site targeting and exclusion, those features limited the breadth of an advertiser's choices on the content network. Now high- and low-value sites can clearly be identified, giving advertisers the full scope of Google's vast publisher network and clear management capabilities at the same time.

"It will allow us to test more contextual opportunities with Google than we would have otherwise," said Brandon Heagle, vice president of client services, Flying Point Media. By combining the Placement Performance reports with Google's other analytics tools, agencies can give clients a comprehensive view of their online ad performance. "We can define the audience that's responding to a client's message and then target them more effectively," Heagle added.

Google rolled out the placement performance reports "in response to advertiser requests" for greater transparency and control. While industry analysts said most ad networks have been headed in that direction, some agency executives cautioned against choosing for or against specific sites based on the initial Google AdWords reports. "We still have to run campaigns the way we've been running them, but these reports give us the flexibility to really see where they're successful," said Muzzy.

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