Sin City. I've only read a few of the Frank Miller comics it's based on, but I do consider myself a Frank Miller fan. And the trailer looks pretty cool. I think the idea of really making it look like the comic could ultimately be a bad idea--intense style is often used to make up for a lack of good storytelling and direction (*cough* Tim Burton *cough*). But if Rodriguez can pull it off, it will be awesome.
BUT....I have to say I'm not too happy about the presence of Bruce Willis. And these words just fill me with dread: "Special Guest Director Quentin Tarantino."