I really liked how they handled Edmund. Made me believe in him, and made me more sympathetic to him than in the book, too.

I also liked the sense one had that each of the siblings really did have distinct relationships with each of the others.

And Edmund's betrayal of Lucy after his first visit to Narnia still has the ability to make me every bit as uneasy as Aslan's sacrifice. Maybe more so. It's the single most uncomfortable moment of the book, for me.