I think there is a difference but I'm struggling to articulate what that might be, though I think the obvious point would be that an omniscient narrator's knowledge (can be) is organized according to some logic that's not neccessarily present with River's knowledge; I think there's also an aspect of forknowledge that (can be) is part of an omni-narrator's knowledge, but really I'm just struggling with digging in and really defining narration, which I've been puzzling over for a couple of days, since author != narrator != character (unless the narrator is a character), and both the author and the narrator impose story upon events in a way that most characters don't.

I also think omniscient third-person narrators usually become characters, themselves, because straight omniscience is just impossible to convey; there must be some order, bias, etc, and that bias becomes the seed of a new perspective that's just as blind in its way as limited-third.

Must clean room now. Ick. Happy Sunday, though! :)