Never before have have I been so constantly on the verge of tears, almost the entire way through playing this, this game cements that walking simulators have their place as a method of storytelling. They're not quite a game (games require a failstate), and they're not quite a film, they're a new form of interactive fiction.
I'm not totally sure about the unfinished swan reference halfway in, but it only lasts a few moments, and doesn't detract from the experience too greatly.

The only other game I can realistically compare this to is The Hex, with it's total changes in gameplay style throughout the entire game, each level arguably being it's own game.