In its attempt to tap into the flood of advertising revenue, Microsoft on Wednesday made its pitch to the representatives of hundreds of major ad agencies and marketers (including Target, Nike, Procter & Gamble and Johnson & Johnson), who were attending the MSN Strategic Account Summit, reports the Seattle Post-Intelligencer. Google, too, was a looming presence at the powwow - though not a physical one.

"They've done a great job on their search, and what they've done with advertising," Gates said of Google, but Microsoft, he said, "will keep them honest in the sense of being able to be better at a number of those things." He added, "I think this is a rare case where we're being underestimated."

Microsoft showed the ad execs its latest online services and programs, many of which include new opportunities for advertising - including Windows Live Mail Desktop, which runs from the PC hard drive but includes a space for a display ad. "We are very, very serious about advertising as a business model across the company," said Blake Irving, corporate VP in the MSN division.

Advertisers will also have access to Windows Live Spaces, Windows Live Safety Center, Windows Live for Mobile, Office Live and Office Online and Xbox.com.