Don't know... maybe fake, maybe not... It is possible that this is really GTA V, but with these pictures there's no way of actually telling.
@Map:
I have to admit, it looks a bit too small to be "the biggest environment R* has ever made", but if you look closely at the Los Santos map, you can see that there are side streets marked in grey, just as they are in GTA V, so maybe this map isn't so small after all.
And I have to say I do like the general concept with the little towns, the big space between them, and also the mountain and lake in the north. And I would like to hit the road on these long highways.
Also, if this is the map, then I am quite sure there will be some kind of Sherrif's Department/State Police/Highway Patrol as the rural areas make up more than half of the map.
So, to sum it up, I do hope this is GTA V's map - also because if the game is this far, then it won't be so long until release...