Any big feature change makes for a good slide or two in the keynotes. They get once or twice a year to make a big impression on the press - dribbling out updates to core apps in the meantime would remove the buzz.
It's certainly made a big impression, though perhaps not the kind they were after. Revealing something in a keynote talk leads to more scrutiny so making a big deal out of something that isn't ready doesn't seem wise to me.
Maps are operating system features that any application can rely on being present. Their are OS APIs that require that the mapping infrastructure be present.
Can't the APIs stay constant while the supplied data/backend gets changed? After all, isn't that the whole point of having a public API so that the implementation can be changed without changing the calling apps?
They could, but Core Location in iOS 6 uses the backend data for things like getting your car route. If I recall correctly Google doesn't let you use their api for things like that.
Basically removing the Maps app is one thing, removing new OS features that use the same frameworks is another.
That is what I said. My point being removing/adding Apple Maps isn't the hard part, it was merely to point out that there is more to the mapping api's than an application. And if legally Apple cannot do turn by turn using Google apis, then they cannot provide one to one compatible api's with both. So they just dropped the Google api backended MapKit.
Map data will certainly be updated constantly, not even requiring an update to the app. Any time there's a road closure or the map changes in some way, it needs to be reflected live. So I wouldn't be surprised if other aspects of the map are updated server-side as well.