I've not read the books, but she has, and she said it was a fairly faithful adaptation of the novel. As a film, I thought it was alright. Slick, easy going, nothing special, nothing terrible. I neither recommend, nor tell you to avoid it.
Afterward, I thought, remember when David Fincher made films that were more than that? Seven and Fight Club are so long ago now that I guess this is the real Fincher, with the overblown opening sequence that looks like a mix of a music video and a Bond opening, and a by the numbers thriller that engages you well enough until the end and leaves your mind a few hours later. Ah well. What can you do? Even his good films are by no means the most amazing pieces of cinema you've ever seen, but they look like it when compared to what he's doing now.
My only complaint about the film related to the violence that happens to the female lead of the film, Lizbeth (played by Rooney Mara). There was a strange voyeurism in the scenes where she was raped, as if Fincher was shying away from making them as awful as they could be, knowing full well that they had to not turn the audience off, and this remain, somehow, palatable to the audience. I found it uncomfortable from the point of view that what was happening here was awful, but in how the scenes were put together that was a voyeuristic quality, and in the way that the scenes were made, an almost tacit acceptance of them, as if the non-consensual part of it was not that important.
Did anyone else have that feel?