But the fact that Google is providing this fine service for free certainly doesn't mean, they don't want earm millions with it. And just in case anybody is wondering how Google is going to pull this off, an Article from Business 2.0 has the answer:
The Web is the new operating system. And, in software, the more people who build on top of your platform, the more influential and indispensable your technology becomes. Once you've established dominance, you can figure out how to use your platform to make money. If local ads become the next large growth market in search, wouldn't maps be a great place to show them? Google's AdSense places text ads on other websites; the same thing could be done with maps. The company could call it MapSense.
Link: Article from Business 2.0