Uhmm no, you're talking about Bandar Desert, largest map in Battlefield's history. And it is nowhere as large as you make it out to be.
Edit: quick google search tells me it's 5 square kilometers. "Bandar Desert is the largest map in Battlefield history, being around five square kilometers large, approximately two and a half times the size of the large map Caspian Border. The map is also shown to have a seven flag variant of Conquest on PC."
Perhaps you're right, but this is what I've found:
http://www.battlefield.com/uk/battlefield3/blog/inside-dice-building-our-biggest-battlefield-map-everIt’s official: The biggest map yet
In Conquest Large, Bandar Desert is stretching as far as 1,900 meters from U.S. to Russian deployment...
That is little more then one mile! To be fair, the terrain would extend slightly beyond that for visual reasons but it's clearly unnecessary to extend beyond two miles and the terrain is probably only 2000 meters square.
I don't have a complaint with you specifically, or anyone else, but the comparisons between AH and other games are almost always exaggerated. Posters never quote accurate specs for any of the games, including AH, and it's become very annoying. Forty miles x forty-eight miles, really? That's laughable but typical.
Anyone can post screen shots, but these are three dimensional video games. I occasionally take screen shots of high res YouTube postings of competing games. What I see is about five miles of terrain before the fog/haze blurs the ground textures, that would be game controlled. Objects start being drawn about three miles away, similar to AH, but that's probably subject to the users graphics settings.
AH could do wonders if they flatten all the ground verts and hid them behind a blur at 5 miles or so, but that would eliminate mountains because mountains would kill suspension of disbelief when they pop into view. I don't think I'd want to play that kind of game.