You know, I've always assumed that making nighttime versions of the maps was originally part of their plan that just never made it to fruition with the deadlines Lightbox were under to get this on the shelves in the dry season for new games. As others have said, everything already has it's headlights on... there must have been a reason for that in the first place.
Maybe Sony will let them do that in a future update or DLC... maybe.
they are addign 6 new amaps in 1.4. the tiny Dust map will probly be focused in White Sands or teh Maw of dispair, both were night in campeign/co-op so good chances there. also the other 5 also have chances to be at night.
There will come a time when day/night transitions happen in Multiplayer next gen. For this one yeah pipe dream.
check Dust514 out. they focosed alot on the wourlds (but they suck at makign a ballanced game, idk if tis worth telling them that they need to fix this and that, especilly since they just made the RPG an anti vehicle AND anti unit weapon, sad thing is, it was allready fixed and they undid it *facepalm*)
but I think SH can have night maps SN, they allready have a few.