Looks like fan artwork to me. As far as I'm aware, Marvel has yet to officially comment on Civil War. It's probably true. Tho some rumors (like Sony leasing Spiderman to Marvel studios) seem highly unlikely.
Could be, I haven't really dug deep into it but I'm pretty sure it has been confirmed.
So the idea that MOS somehow opened the door for superheroes from Gotham, Atlantis, and elsewhere, seems very very forced.
It was a nod that others heroes existed in this world and others will exist regardless of the plot to Superman. MoS was Superman focused but there were nods that imply that this is an open universe, something the Bat-Trilogy pounded its chest as to what is wasn't intended to be and how TDKTrilogy was a world where only Batman existed. Snyder didn't go out of his way with other nods to heros, but the implication is there and was placed for that sole reason that they're out there.
The Man of Steel oil rig scene was significant to Aquaman as well. That oil rig was named after the company Arthur always had problems and tension with so that oil rig scene was certainly a nod to the King of Atlantis.
But they are not even in pre-production.
Yeah, I fucked that up. I meant they are in studio development. They obviously aren't in production as Snyder and the entire cast of MoS; BvS will return for Justice League Part 1 (a two-parter) which is cool that Justice League will follow a continued connected story. I expect the solo Supes/Bats movies to either come right in between Justice League Part One and Justice League Part Two. Maybe one for before part one and one to set up Part 2. It's a logical placement DC is saving for.
From Forbes:
http://www.forbes.com/sites/markhughes/ ... confirmed/
It’s also possible that the Man of Steel 2 film — confirmed as in development, so Superman fans rest easy, okay? — will end up on with a 2020 release date, and there’s a solo Batman film confirmed as in development that could either get a 2020 date or might even end up popping up sooner on the list. We’ll have to wait for confirmation of release dates on those, but both films are planned for release by 2020. For now, the confirmed films and dates should go far toward making fans happy for the next several years.