Google has built the most powerful brand in the world with nary a bit of brand advertising. But as ads for Google Maps crop up on buses in San Francisco and trains in Chicago, it's clear the company is willing to shell out ad dollars to grow a product that's key to both local and mobile search. The branding push promotes the service's transit features and comes at a time when Google is courting brand advertisers to buy online display ads, TV and radio. Incidentally, its own campaign focuses on the one medium Google hasn't dabbled in selling: outdoor. A quick search on Flickr (sorry, Google Image Search) reveals about a half dozen Google ads uncovered around the country in the past six months, including bus ads and train wraps in the Bay Area, a wrapped El train in the Windy City and street teams in both cities that demonstrate the product for passersby. There was also an ad in San Francisco's AT&T Park. Federated Media's John Battelle spotted that last one and posted it to his blog. “You might call it a non-[cost-per-click] banner display ad in the middle of the Web site that is AT&T Park,” he said, noting that only a year ago, Google VP-Marketing David Lawee told BusinessWeek that Google does a lot of direct marketing but “not brand marketing.” But Battelle said brand marketing is inevitable for Google (even if you have the best product in the world, you have to tell people about it), and he's not alone in that line of thinking. “Google was successful initially because it had a search function that was demonstrably better than what it was at the time and people were recommending it,” said Nigel Hollis, chief global analyst at Millward Brown, which recently named Google the world's most valuable brand. “But because they've been extending their portfolio of solutions, there's now a mass of things they offer that perhaps many people haven't gotten to know about.” Many mapping services today have the same features, making them harder to differentiate. Google is hoping that offering trip planners and fare information for local mass-transit services will help demonstrate its superiority. Google likes to let its products speak for themselves, said Nate Johnson, product-marketing manager for Google Transit. He describes the ads around the transit features for Google Maps as giving them “a little bit of a nudge.” That nudge is important because while revenue is arguably small today, maps are considered key to nabbing the large and growing pot of local online and mobile ad dollars that advertise around them. And while Google Maps and its many mashups seem ubiquitous, it still trails AOL-owned MapQuest in total usage. However, the mapping sites' momentum has shifted since April 2006: MapQuest's share of U.S. traffic among all Web sites is down 5%, while Google Maps is up 307%, according to Hitwise. “This is a popular consumer product, and Google is promoting it as part of its long-term strategy to win, grow and maintain usage,” said Greg Sterling, principal of Sterling Market Intelligence, which specializes in local online advertising. It's also, he said, an “early killer app” for mobile, as Microsoft, Yahoo and Google all have mapping applications delivered to mobile devices. There's not a noticeable volume of advertising on the site: A search for “restaurant” while looking at a map of Brooklyn, for example, displayed one sponsored listing—for an Italian joint in Jersey City, N.J. A hotel search on a map of downtown San Francisco displays small logos of several major chains in the area. By contrast, Microsoft's Live mapping product has a deal with Yellowpages.com to deliver local-sponsored links. And AOL's MapQuest is chock-full of sponsored listings; simply pulling up a residential address in Brooklyn revealed more than 10 sponsored offers. Abbey Klaassen is digital editor of Advertising Age, a BtoB sibling publication.