Ok. I was able to flawlessly upgrade to 5.1 from 4.7 on my BB 8700c last night. I am very pleased by the new software. I decided to make a list of things that I have found to be new in the 5.1 version. Some might be running different versions of 5.1.x.x etc. So, I am not sure if these apply to all. I also know that there are a couple of different threads. This is just a new feature - might not have noticed - thread. Not for upgrade issues or bluetooth pairing etc.
Here are the things that I have noticed that might not be really obvious or not easily found in the instructions.
1. You can have the "birds eye" map follow you even though you are not going anywhere specific. Go to Maps and Traffic --> Current Location (it takes you to a 2D top down map) ---> Then click to get to "3D Follow Me Map". It is a moving, 3D map!! The maps shows the street names of the streets that you are crossing but does not seem to show you the street that you are currently on or any other info like speed, direction etc. Not exaclty intuitive to find in the menu system.
2. Drive to Cursor - While in static map view, you can move the cursor with your trackball/wheel, find location that you want to go to, then click to get to "Drive to Cursor. This makes a quick way to go somewhere you see on the map but don't wanna try and figure out the intersection, or make a waypoint. Just Click and Go!!
3. Estimated Time of Arrival. The ETA seems to be dead on. In the navigation mode there is an ETA that is much better than the old version. I have only driven 3-4 times, but it has been dead on for my ETA. within 1 minute. Pretty sweet!!!