AdAge said the consumer-related assignment has drawn pitches from Microsoft’s current agency, McCann Erickson, which handles most of the Microsoft ad business. At least one other firm is believed to have made a pitch at the assignment too.

Microsoft intended for this ad review to stay quiet. But the company spent $912 million on advertising last year; a single spend of nearly a third of that had to attract attention.

As to what Microsoft plans to advertise, they aren’t saying. AdAge speculated it would be something to hit back at Apple’s popular “I’m a Mac” advertisements.

We’re going to guess it will be a push to promote the Vista operating system among consumers. Microsoft had to swallow some pride and allow OEMs to offer Vista’s precessor, Windows XP, to customers beyond the original cutoff date for the older OS.

Operating systems and the Office productivity suite represent Microsoft’s big revenue channels. If people continue to disdain Vista over stability issues, or worse, buy an Everex PC running Linux, Microsoft may plan the ad binge at keeping customers buying Windows machines.

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