Well, like Engadget mentions, they'd already broken Maps out like that a while back. The entire reason they can do this is because they've kept their first-part

Well, like Engadget mentions, they'd already broken Maps out like that a while back. The entire reason they can do this is because they've kept their first-party apps out of the system level and exposed the functionality they need publicly. The official Facebook and Twitter apps integrate with system contacts, for example, not because Google integrated them at the system level, but because Google provided an API to allow this with the Android 2.0 release. One of the things that continually impresses me about Android is the fact that Google took so much care to create a clean architecture that opens up the door to a lot of cool opportunities for any application developer.