Watched Constantine last night, and I enjoyed it quite a bit. I thought it was good, but that's grading it on a scale for comic book movies. It's by far the best occult/angels/demons type movie I've seen, but its competition is Underworld and Van Helsing, which were each different varieties of lame. Constantine did a really great job with Gabriel and Lucifer, and hell looked pretty interesting. The movie had a pretty good use of color overall, wasn't the stark, high-contrast, washed-out look I generally would expect from such a movie, but everything managed to look clean yet ragged and dingy at the same time. The pacing feels different, but that's probably just because it's paced more like a comic and less like a movie. You take for granted how movies are all paced a certain way, how scriptwriters insert X action beats in the first 30 minutes, etc. In this case, the action seemed to follow the plot a bit more, which I don't mind. The tone seemed to successfully mix the cynical apathy of Constantine with some playful moments, and definitely made the movie for me. Anyway, long story short, it's a pretty good rental, IMO.

I'm definitely going to pick up some of the Hellblazer graphic novels since I've heard good things about them even before the movie came out.

Edit: Forgot to mention, John Constantine is supposed to be British, and the stories usually take place in London, and the movie is Americanized fairly well. I thought it was fine, as have most fans, so it's not too bad. Keanu Reeves is pretty good in the role (he just has to act jaded and apathetic most of the time), but I don't think I could have taken him seriously with a British accent.