Yesterday, Google formally let the world know what it has hinted at for years and what we’ve all known, from personal experience, would happen one day: We use smartphones to look up things on the internet more than we use desktops, laptops and tablets—combined.

We’ve written about it many times, but now it’s official: “We’ve hit an inflection point,” Google’s Jerry Dischler told VentureBeat yesterday. “There are now more Google searches on mobile than on desktop in ten countries, including the U.S. and Japan.” (Note: Google considers iPads and other tablets as desktop devices, so “mobile” in this context means smartphones, primarily Android and iOS.)

Also as anticipated would happen at some point, Google unveiled entirely new types of ads it will be offering for smartphone advertising.

While this first wave of new ad units are focused exclusively on travel ads and car ads, expect to see such ads rolling out soon to include all types of services. And expect “local” search to be a major focus, eventually.

The new ad units are native to mobile—they don’t port over to the tiny screen, the types of ads seen on desktop and laptop computer screens. The first generation of these ads are like photo gallery tours of a car—inside the ad. For hotels, the ads can provide the user a means to price and book a reservation—inside the ad. Later this year, a similar mortgage-finding ad unit will allow users to find rates, compare options, speak to an advisor—all from within the ad.

The new ad units could change the “pay per click” paradigm

One of the biggest challenges facing Google is to attribute off-line purchases to online advertising. This is especially challenging, since Google has trained the marketplace to pay for “clicks” and not impressions. With the new mobile advertising units, Google is trying to provide data that links actions taken within the context of an ad to purchases made later, offline. By doing this, Google opens up the opportunity for more profitable forms of lead-generation fees from advertisers. According to VentureBeat, the new units will allow marketers to track journeys from desktop to phone to tablet, and attribute revenue to ad spend accordingly.

Why should small businesses be interested in Google’s new mobile ad units?

The New York Times made this observation about consumer search patterns: “One big difference between mobile and desktop computers is that it can be awkward to click on things. And people start searching when they are closer to making an actual purchase.”

As search has shifted to mobile devices, the kinds of advertisers Google must serve (even more than it does today) are going to be local merchants, restaurants and a vast array of service business ranging from auto garages to dry cleaners. Mobile search will become more-and-more a battle between Google and Yelp, TripAdvisor, Facebook and others.

Immediacy and nearness are critical to mobile search users. And that means all roads (and mobile search queries) lead to local.