I've been able to use Google Maps to show my location on my Verizon 8830. Most of the time my location is show 'within 5000 meters' of my current location - and it's usually close to where I actually am. In one case, google maps pinpointed my location to the exact intersection that I was at - but, as I moved on, it failed to update. I would have thought with VZW locking down the GPS that Google maps would be able to locate my position at all - but now I'm wondering how I can set it to come up with a more precise location.
Google Maps is using tower triangulation to approximate your position on the map. This is a new feature which Google implemented with Google Maps 2.
It is NOT using your 8830's internal GPS. (It's not using GPS at all.)
Sometimes it's somewhat accurate, sometimes it's not.
All depends on where you are and what towers your device is receiving signals from.