I've only seen the iOS and Android version for like a glimpse so I'm not really sure how different it is in terms of the UI. But the main navigational parts looked similar showing traffic situations on main roads and also tracking your position. Of course they try to match the other parts in line with Window Phone's Metro UI layout. The good for me is of course the ability for it to measure traffic based on input by other users. I sometimes report it as well. Whenever I think I need to reach a destination fast, I'd use the app to find out the best route and what time I can reach there. At release, it's already packed with lots of features. I get to search destinations by Waze, Google Maps and Foursquare, look for nearest Petrol Stations, ook at reports by users, set up accounts and manage it and more.
The not so good for me is that it always seems so hard to get GPS signal. I'd get it in one instance, then when it's lost, it took a while to come back. I needed to put it right at my window to get back the signal. Because of this, I sometimes miss turns and it had to recalculate my route. Even detecting through data where I was was too late to tell me the turns I needed to make. During rush hour, it did manage to find a fast route to get to my destination by using inner roads but it does make me wonder if it considered the traffic light stops in between. Like yesterday, I was from Damansara going to Kajang during rush hour. It took me to an inner route just to get me to the KL-Seremban highway which I could've done by going through the Federal Highway. Maybe Federal was at a standstill. Not sure.
Overall, I would use it if I wanted to find out the fastest route home to estimate the traffic. To use it as GPS, I'd better get familiarized with the routes it's going to be taking or else I'll get even lost. Here Drive is still my preferred GPS app.