just a random thought but...shouldn't the military base be in the northwest ?...i mean , it's the only clear space you can find on any fan-made maps and if i remember right rockstar (or the guys who saw the demo) said that the game includes a military base
here's a fake map (or is it?)
http://www.youtube.com/watch?v=Si-f34VbiAs
i'm pretty sure it's fake though because rockstar never "leaks" something so important , like the map , but it's the best fake i've seen so far