I've heard people rave and rave and rave.
I've read this review at The Playlist where they loathed it. Shredding it in true pretentious Playlist fashion. (Love you, Playlist...)
I'm definitely somewhere in the middle. It's over long and there are some debatably unnecessary character building tangents. But I enjoyed the movie. I was entertained, and the title character was unlike any character I've seen before.
She is a hard core, pierced, motorcycle riding, computer hacker that no one should mess with. She sleeps with men and women and she keeps her thoughts and feelings to herself. She's the movie. She's what's unique about it. The Playlist was not a fan of a sequence in the first half hour or so where she gets revenge against an (overly) evil probation officer. I was on her side with that revenge. And I was shocked. I think this sequence does what it's intended to - it tells us what she's like and if you don't like it (or her), stop watching now.
It's true that all of the characters apart from her are fairly cookie cutter. I would argue that with her character being so different from what we're used to seeing, it's not unreasonable for the author (or screenwriter) to keep the rest of the cast fairly understandable.
The plot is a plot. It's not genius. It's not absurd. Mysteries aren't typically my bag. They tend to be either obvious or so ridiculously complex that no movie goer could play along. I'm never going to be particularly interested in the mystery itself if only because I know the ending will (almost) never live up to the twists of the plot along the way. (Shutter Island is the first movie in a very long time where I found the ending to be as cool as the journey). This movie had Lisbeth, and I was content to watch her be sort of awesome.
This movie gets talked about. For that reason alone, I would recommend it. Nothing drives me crazier than people with strong opinions about movies they haven't seen (or books they haven't read or musicians they haven't heard). It's an entertaining watch. It's got some graphic sex stuff so beware of that. But The Girl With the Dragon Tattoo is a cool chick and I look forward to seeing the sequel.