I'm on day two of my windows phone experience, and while I'm not willing to conclude "junk", the navigation experience IS disappointing.
The need to tap on the phone id a deal breaker, frankly. In Pennsylvania, it's now illegal to interact with your phone while in motion. In other words, it'd be illegal to use WP navigation.
someone mentioned that he likes tapping at each turn. I found a flaw there, though. When I made a wrong turn, Nav helpfully told me that id done something unexpected. Of course, it wanted me to tap in order to get modified directions. Pardon? What good is it if my Nav program presumes I don't want to recover an error that I've made? Ok -- so, we're stuck with the modal "tap interaction" model. However, when I tapped... I got nothing. No response, nothing. If the answer was "sorry, you're screwed", then it should tell me that, not leave me wondering whether the program had gone unresponsive (it hadn't)! Even if the response was "exit and turn around", that'd be something.
I decided to re-enter my destination, in the hopes it'd crank up a new set of directions. No luck... Voice entry failed four or five time in a row, until I gave up (after all, how many times can you say "dogfish head alehouse" and get a "sorry, I didn't get that" reply before you give up?
on the other hand, I DID like the fact that Bing pointed out a landmark at one of my turns. It might have been helpful had it mentioned the side of the road it was on (I was looking to make a left, and the landmark was on my right. Ouch.)
Some minor quibbles: I had to configure the app to rotate the map as i turned (does anyone find it intuitive to