Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
iOS 6 Feature Flyover & Turn By Turn Navigation Will Only Be Available On iPhone 4S, iPad 2 & Newer
We were expecting Apple to announce new maps today but they wowed us a little with Flyover and turn by turn navigation.
According to Apple’s website these features will only run on the iPhone 4s , iPad 2 and the New iPad. This means that the iPhone 4 & iPhone 3Gs will not be able to get access to Flyover or turn by turn directions
Some features may not be available in all countries or all areas. Flyover and turn-by-turn navigation will be available only on iPhone 4S and iPad 2 or later. Cellular data charges may apply.