I don't know all of Sayles work, but I plan to. This film really impressed me.
What I look for is a few things, that if done well will really satisfy. Among them are:
--daring use of the cinematic medium
--transporting me to a conceptual space that I otherwise wouldn't have experienced
--self reference
CINEMATIC: Sayles is a storyteller, who thoroughly understands what it means to build a narrative scaffold using film. This is theater completely recast for the unique strengths of film, and only possible when the same person writes, directs and edits. This camera is literally introduced as a character when noelle offers it an `hoordoov.' The camera participates, the lights participate. We have overlapping dialog, overlapping cuts, multiple views of the same scene. We have long panning multithreaded scenes. We have a dramatic pacing which starts slow, sets a lot of potential threads and convincingly fools you into relying on certain expectations.
Then narrative commitments are made before you are ready, and then come faster and more unexpectedly until the very gutsy end. Sayles knows in real storytelling, there's a game between teller and listener, each trying to outwit the other. A masterful storyteller teases but plays by the rules, allowing the reader to take risks. It takes craft to do this in the written word, and is extremely rare using the more intimate but external and slippery experience of cinema.
TRANSPORTING: Alaskan wilderness as theme park where stories are safely refined for casual visitors. That would be enough given this level of craft. But Sayles takes us into Noelle's diary world. That's the center of this film's world, the world of the mystical Shefox. Deep imagery here -- superficially referenced in the `real' action. I do not expect to ever forget that visit. The self-reference is in both.
Much has been made of the actors, and I think that a mistake since the creative force here is clearly Sayles. But this girl Martinez has some magic. Who will write parts for her?