- First and foremost, the game will take place in Boston, and be kind of a direct sequel to Fallout 3 with a few groups returning.
- From what it sounds like, "The Institute" is pretty much the downtown DC or New Vegas of this game. Boston is going to be unlike anything we've seen in a Fallout game before, with buildings more on par with cyberpunk and retro-futurism.
- Androids play a big part in this game. The railroad from Fallout 3 is a faction. The enemies of the railroad is "the Plantation" -- a group who force Androids to farm so that Humans can get food. The Institute is highly advanced and probably obtained or built their own GECK to start a farm.
- Due to complaints about using Super Mutants and the Brotherhood of Steel in Fallout 3 excessively and going against the lore too much, - Bethesda has decided to avoid using these groups. Bethesda wants to make a new "race" (think Ghoul, Super Mutant) which will be central to Boston. Bethesda is currently looking at Lovecraftian fiction since Boston is around "Lovecraft Country".
Bethesda has no plans to reinvent the leveling up system to make it more like Skyrim and want to make Fallout 4 more distinct from Skyrim since of the complaints that Oblivion and Fallout 3 were too similar. Bethesda is thinking about introducing a system, similar to Skyrim, where your skills can level up if you perform certain tasks.

www(dot)reddit(dot)com/r/gaming/comments/16cgj0/pal_of_mine_works_in_public_relations_at_bethesda/

Oh, look, another redditor claiming his friend works at Bethesda. Because those have always turned out to be true.

Yeah right, I'll believe it when Bethesda makes an official statement.

Lot of leaks came from reddit. Most of the Mass Effect 3 dlc leaks were posted on reddit and all became true, etc.

Last time this happened a Bethesda employee outright said it was false. You can't trust anything you read on the internet unless there's proof.

Besides, most "leaks" turn out to be false. Just because a few turn out to be fairly reliable doesn't mean they all are by default.