Yes Apple want to own maps on iOS but given how their own launch went the ship has sailed on that for a while at least. But given the position they found themselves in this goes a long way to undermining the criticisms of mapping on iOS because if you think Apple maps sucks you just go and get Google maps for free.
One of Apple's big gripes supposedly was that they couldn't get Google maps turn by turn navigation on the iPhone and here it is (and without them paying for it it seems) plus they get to work on Apple maps with some of the pressure off which protects them some if Google start messing around.
I'm not in any way saying that this was Apple's plan all along - that plan went badly wrong in the summer - but as of this morning iOS, for regular users at least, just got more attractive.
Yes it's a win for Google, but it's a win for Apple too.