Anil Dash has a well-written takedown of Apple’s new Maps in iOS6 on his blog:
But the simple fact is: When you buy an iOS 6 device, you get a worse experience for search and no ability to get transit directions out of the box, both of which are significant downgrades from iOS 5. Apple’s taken features away (critics would say “crippled”) from apps before, typically during major platform changes or when rethinking the fundamental architecture of an app. But in almost every one of those transitions, they’ve provided a transition period or staged upgrade path that didn’t force users to bear the brunt of the new platform’s weaknesses.
I’m going to give Apple’s new maps a month before giving it a real critique, but Dash points out many shortcomings that will annoy a lot of users.