Batman-on-Film has a brief description of the mask that will be worn briefly by Cillian Murphy as Jonathan Crane in Batman Begins. Spoilers ahead!
[It seems] The Scarecrow will appear in FULL costume during a [fear gas induced] hallucination towards the end — Arkham perhaps. Also got to see a pic of the actual mask–let me say this thing is f’ing disturbing; really, this thing will scare the s##t out of you. It’s a very dark drown, it had no hat and no hat will be with the sack. The eye holes were scary to look at with no eyes, so what they will look like with eyes is anyone’s guess.
Meanwhile, the Chicago Tribune reports that filming in Chicago will take place for six weeks starting in July. And veteran actor Rutger Hauer also indicated on his official website’s guest book that he’ll be playing Mr. Earle, a Wayne Enterprises executive.
Source: Superhero Hype!