There are spoilers that follow. Moriarty's look at the script basically covered the introduction to the story, but I want to cover why this movie is going to just about be as cool as cool can be. God, I get chills before I even type it. When the Headless Horseman gallops through the forest at night, the trees get out of his way. The forest parts.
Corn stalks bend out of the way, grass shrinks away from the hooves.
The one thing that I have to stress here is that this is not our typical Tim Burton story. Self mutilation, adultery, hangings. Ichabod is intelligent, he's not some sort of cowardly fella, he's a man of science forced to deal with something beyond his understanding. He is both Mulder and Scully. It also has the 'keep ya on your toes' mystery of Andrew Kevin Walker's other scripts.