I can't tell you how I know this and I can't give you proof that I know this. NDA's are a bitch to fight and I'm not losing my access for you fuckers.

There are 17 fully-fledged towns with some smaller "towns" that are more like points of interest, kind of like XY's berry farm and that mansion you can visit on the same route. Not really towns, but non-wilderness locations.

One of the islands is almost entirely wilderness, that is where the majority of endgame occurs as well as the climax of the story.

While Alola is primarily based upon the American state of Hawaii, it takes from other American landmarks as well, namely Yellowstone National Park, Yosemite National Park and the Grand Canyon.

Battle Frontier does make a return, though it's not quite how it was before. Some things returned, some didn't, new things were added.

Similar to XY, the evil team in both games are the same and have the same end goal. In my opinion, this is slight laziness on the developers'/writers' parts, but the game is still pretty original in its story overall. It's gonna be different from any other game before, with a lot more depth and actual motive behind the enemy team.

Any questions? I don't know everything, but I do know a good amount of content.