Well, this may or may not be related - Google Maps were absolutely horrible in terms of reliability in my area, but very very recently, the 14 updates that I submitted (4 of which were flat out refused b/c
... [they] could not do anything about it
- they tried telling me that they could not change the name of a couple of surface streets they had misnamed...) all of a sudden 9 out of the 10 they said they would fix they fixed. It was nice, this afternoon, for the first time since I have had the DROID, to set my home as my destination and to get accurate directions
and when I arrived my view changed from a bird's eye view to a street view of the front of my house....
Very nice....
The reason I bring this up is that, up until the huge Map update, I suppose that Google had not actually tagged your area as a Military Base, and thus the GPS would get very very specific - however, I am guessing (stabbing in the dark?) that now that Google has your base appropriately marked, that they may, in fact, be disallowing precise GPS coordinates to be used in non Military / Government / Emergency situations....
Like I said, it is just a thought - I may be way off base here (pun intended

) but then again, *I* sure as hell would not want classified info such as secret room / building locations to be easily taggable on a Military base, yanno?