In my experience, Apple’s Maps has a better interface and updates faster for missed turns than Google Maps or even TomTom. Its traffic reporting is the weakest of the three (and is why I spent the money for TomTom), but its greatest weakness is the points of interest database (which I think they licensed from Yelp). If you have a street address, Apple Maps is great. If you’re looking for the nearest drug store, less so.
I haven’t done a lot of testing with it in the last year or so, so it might have gotten some recent improvements.
It has. My girlfriend and I used it yesterday to navigate to a dinner invitation at a friends apartment. There was heavy traffic on the primary route which it showed and automatically routed us around the traffic to save us about 20 minutes on the trip.
It still has trouble with closed stores, but so does Google Maps. I have done comparisons and it's about 50-50 which gets it right. Google Maps showed a bank I was looking for as being open and the building was not even there anymore. . . while Apple Maps showed the correctly located new bank several blocks away, and the newly built fast-food restaurant where the old bank had been located. Other times Google maps will show the correct data and Apple Maps will miss, showing a restaurant that closed years ago as still open and the attached Yelp data still containing rave reviews and no indication that the place closed down and is now a Laundromat. It can be frustrating either way.