A paragraph from Google's announcement also notes that Google is considering (no surprise) placing advertising onto Google Maps in the future.
The API is open to commercial and non-commercial websites that are free to consumers. Google will include the Google logo on the map, a link back to Google Maps and may show ads in the future on the maps.
Full Text of Google Maps API annnouncement.
Meet Your Favorite Search Engine Watch Contributors
Many of SEW's leading expert contributors will be at ClickZ Live, the new online and digital marketing event kicking off in New York (March 31-April 3). Hear from the likes of: Thom Craver, Josh Braaten, Lisa Barone, Simon Heseltine, Josh McCoy, Lisa Raehsler, Greg Jarboe, Dan Cristo, Joseph Kerschbaum, John Gagnon, Eric Enge and more!