My dog walker has become the latest weapon in the escalating search engine marketing wars.

Since I first met Rodney Dorival, owner of Big Paws Little Claws, I’ve thought he could just be the next Cesar Milan. He’s amazing with dogs, erudite, unfailingly charming, drives an immaculate, celeb-ready ’68 Buick Skylark that he restored himself, and as you can see from the photo he looks like the linebacker who gets the brand endorsement work (the arms come in handy for keeping my skateboard-chewing Rottweiler under control.) So I guess I shouldn’t be surprised that Microsoft also saw his potential and recently decided to turn Rodney and his staff into a marketing channel, wandering the streets of New York in T-shirts emblazoned with the Bing logo and search box.

I’m pretty skeptical about ambient media. When I was working for Ad Age I was frequently bombarded by press releases from people who thought that their network of hubcap-cum-tea trays or toilet seats that double as frisbees, were the perfect branding medium, and I tend to think this stuff is just commercial clutter best avoided by brands. But for Bing, Rodney’s crew seems a smart choice.

Sean Carver, director of brand entertainment for Bing, explains why he did the deal: “Dog walkers make constant decisions about where to go, and get asked for directions and help all the time too. They’re also inherently expert on their local areas, and we wanted to stress that one of our strongest feature is the ability to find what you want locally. We’re trying to humanize search, to put the person in the middle.” And, as Rodney himself points out, “we’re walking billboards surrounded by dogs that people want to stop and pet, what could be better. I’ve always used Bing’s visual search to research my clients’ pets, so Microsoft seemed like a natural partner.”

PR maestro Keith Estabrook who represents Rodney (yes, my dog walker has a publicist, the same publicist as Lebron James!), connected him with Microsoft, and has helped them get some nice earned media on the back of the sponsorship with Rodney appearing in the New York Times and on CBS’ Early Show, sporting his Bing t-shirt. Bing is now planning to sponsor dog walkers in Chicago and San Francisco, and is also working on a map app that’ll help people find their local dog parks.

Of course there’s a bigger story behind this, in the shape of an escalating marketing battle between the search engines.

I confess, I was one of those people who figured that search would always be simply a case of ‘best engine wins’ and that no amount of marketing dollars would change Google’s hegemony. But Microsoft’s big ad spending appears to be working with its search share having jumped about 4% to almost 12% of the market since its Windows Live search was revamped and relaunched as Bing last June.

Google’s hardly on the ropes here. Bing’s gains seem to have come more at Yahoo’s expense, and Google has maintained its 65% share of the search market. But Google is still totally dependent on search despite all its other fascinating moves, and is clearly becoming a little more attuned to the idea of openly marketing its services, witness its show-stealingly beautiful Super Bowl spot, and the follow-up Search Stories Video Creator. (It’s also interesting that it has launched a revamped search interface this week, and while Google’s PR around this revamp has stressed that these changes have been in the works for a long time, the new interface does have a certain Bing-ness to it.)

So it seems likely that the search marketing wars will continue, and maybe even escalate, after all the battle over mobile search, which will surely be a bigger market than desktop search at some point in the future, has barely begun.

In the meantime Rodney Dorival continues to build his burgeoning business. He’s already lined up a second advertiser for his newly-minted media network, a manufacturer of glass products called Glassybaby. But his main ambition is to continue to build his core business, which he sees not just as dog walking, but as a petcare concierge service. “Whatever you need that’s related to your pet – from picking up dogfood, to taking a trip to the vet, or anything really – we can provide. I think we can change the way the petcare industry is viewed.” And who knows, maybe a TV show? “I wouldn’t rule anything out,” he says cagily, before his publicist steps in and ends my interview with my dog walker.

Jonah Bloom is the CEO and editor in chief of Breaking Media.