Rock, Paper, Shotgun has an interview with Thechineseroom's creative director Dan Pinchbeck, where they discuss Amnesia: A Machine for Pigs.
RPS: So it’s a new setting, and new characters?
Pinchbeck: Yep. It’s 60 years later, the new game takes place on New Years Eve in 1899, in the streets of London, so it’s full of mist, Steampunk, Victoriana. It’s set broadly in the same universe, but it’s not a direct sequel, these aren’t descendants of any of the characters. The underlying mythos of Amnesia is present, but making itself felt in another story, another time, another part of the world. That’s been really great in term of making the game. Even if we’re not making it explicitly clear to the player, the logic of what’s going on, the development team are going “Well that makes sense, because that would fit in there. There are bits where it’s going to be interesting to see how direct a comparisson people draw. For us, we’ve got this amazing playground, fictionally, to build this new stuff off. Because we’ve gone that far forwards, it means we can do all kinds of other stuff, in terms of industrialisation, in terms of machines for pigs.