One of the interesting things about Sin City is that when I think back on the film, I see the comic strip in my mind, not the live action. This is kind of rare. Can anyone now read The Lord of the Rings and not visualize Gandalf as played by Ian McKellen?
Let's face it: Comic-to-Film adaptations suck. They suck because Hollywood gets in there with their fucking retarded fingers and starts messing up the vision of the comics' creator and you end up with this horrible hybridized beast, in which you can see the intent of the original work trying to get through, but not quite making it through acres of "ooh this demographic needs this" shite. As a result, pretty much all comic book adaptations have, if not actually sucked, been pretty pale imitations of thier source materiel.
Until now. Robert Rodriguez literally used the comic as the storyboard for the film- every shot in the film is the extrapolation of a panel from the comic. It takes faithfulness to a whole new level, and as a result the film is very much just like looking at the comic book, in motion. It's almost not even a 'live-action' adaptation, because, outside of the actors, the whole thing is animated. The Maltese Falcon has long been praised as the ultimate noir film- I'd say Sin City not only succeeds it, it invents an entirely new subgenre of pure noir, which TMF and Payback are merely hinting at, but Sin City actually realizes. This film, for what it is, could not be improved- it's the world's first perfect adaptation.
The Hard Goodbye is the first chapter (I've heard that, on the DVD, the chapters will be both more complete and watchable as individual films- I can't wait), and in my opinion the best. Most of the humour relies on the fact that the main character can inexplicably take cast amounts of damage and keep on going. It's by turns shocking and funny and brutal and touching. Mickey Rourke (Mickey fucking Rourke!) is the perfect Marv.
I think TLG has an advantage over the other chapters because you are still getting used to the bizarre visual style of the film, so it seems fresher and more watchable- by the time the third chapter comes along, you're completely immersed in the digesis of the film, and so start to look for more depth in the story, which the film is unable to provide (the 1st and 3rd chapters being essentially straightforward).
The Big Fat Kill (which is a great title!) is a strong second, and a big departure from the linear plot of the other two titles- it's full of twists and turns, different factions each with different motivations, all of which conspired to keep me interested and suprised, even though I knew more or less what was going to happen. The steely deadpan Clive Owen employed so effectively in Croupier seems perfect for a noir film, and the idea of a suburb consisting entirely of implausibly beautiful prostitute-assassins is, of course, a perfect distillation of the world that Sin City resides in.
The big letdown is the last chapter, That Yellow Bastard. I must make a disclaimer and say that I nodded off a few times during this chapter (I'd only just flown in to San Diego that day), but from what I could gather the plot was more or less identical to 'The Hard Goodbye', albeit with a live woman spurring the protagonist forward through ever-increasing obstacles as opposed to a dead one. It's still solid noirish, and good enough to watch, but you just start to feel like they are treading old ground. Ah well- that's what you get for being so faithful to the original text.
I guess the only gripe I would have about the film is that it's not exactly deep or meaningful stuff. No-one's going to come out of this with anything challenging to think about. But really, who cares when it's this much fun? Bravo to Rodriguez for being so faithful to the comic, bravo to Millar for writing it, and bravo to all the big name stars who signed up for an ultra-violent, ultra-sexy, difficult piece that a lot of people probably won't get, but those of us who love comics will just lap up.
I recommend it- highly.
This is a 
Can't wait to see it when it comes out here. Don't tell me any more about it.
Well, you see, there's this cannibal, see, and he's played by...oh, you'll never guess who!!!