Flyover lets you "see major metro areas from the air with photo-realistic, interactive 3D views" and it's a clever combination of Google Earth and Street View. Last year, Apple acquired C3 Technologies and used its technology for the 3D maps.
Obviously, Apple's new maps app no longer includes Street View, Google Transit, Google's comprehensive maps and local search and many users will miss these features. Google will lose a significant amount of mobile traffic and an important data source for Google Maps, but it will be able to release a much better Google Maps app, assuming that Apple approves it. After all, Google Maps is one of the best apps for Android and Google has constantly added new features, while Apple's maps app hasn't improved too much.