Given today's mobile technology (smartphones with EDGE/3G data, Java support, and basic application support), I would say that the integration between Google Maps, Nokia N95 GPS and 3G Data is one of the best mobile experience I've had.
Its a perfect marriages of functionality and usability. Google Maps application for Nokia is surprisingly robust. It offers the benefit of latest map data and POI over Nokia Maps. With "my location" function, Google uses cell signal and the integrated GPS receiver to approximate my location and provides navigation. Since it uses a similiar technology as the iPhone, I can be located even in areas where I have no GPS satelite exposure (indoors). Finally, if you are outdoors with GPS fix, you can use it to navigate to your searched destination. It does all three things very well and until I got my N95-3, none of my previous phones could do all of these together (ie. Apple iPhone or HTC/AT&T 8525).
Take a look at the screenshot for example. I used "my location" to identify where I am at (white dot) and searched for Starbucks nearby. It showed me a bunch of nearby locations. Now I can choose the closest store or the one on my way to another destination. Some may argue that ths is what a real GPS unit does; while I agree that it s what a good GPS unit should do, but having 3G data offers more benefits: 1). It can pin-point your location even indoors, great for pedestrians planning a walking trip in house, 2). With 3G data, it offers incremental information like traffic, and look up a store information via the mobile browser and 3). You will always have your phone with you, but not always will you carry a pocket-sized GPS unit. Considering my feedback on my OEM GPS system, you can see how I would rely on this solution while I am on to go.
PS - Nokia Maps offer some benefits as well. Having the ability to download the maps to your phone directly gives you even more flexibility when you are not able to connect to the web. I used it for my trip to Asia and it was great to use GPS w/ pre-installed map sets of Taipei, Jarkata and Bali Island. One time, I used it in a subway to check for the closest subway station I needed to get off the train. All because of the benefit of having pre-installed maps on my handset.