In my opinion he didn't. I don't quibble with his lopping off a huge chunk at the beginning of the novel. It's interesting but left me asking why it was there. It seems so surperfluous. Perhaps it comes into play in volume three? In any case, the cut was necessary especially when you consider the book was about 650 pages long!
Which is perhaps what went wrong; it's the usual lament - there's soooo much they have to leave out in films. Except in this case it wasn't quite so much the details left out as to the speed which was used to cover the material left in. There was absolutely no time to develop the relationships and story at all so what you ended up with was a "this happened then this happened then this happened" scenario that was simply unsatisfying.
Plus I spent a good deal of time questioning whether one of the key bad guy characters was who he was supposed to be. "That can't be him!" I complained to my husband. "Shouldn't he be younger?" It was incredibly distracting! Yes, Lisbeth can still kick ass with the best of them and boy, is she a survivor. But I felt what was missing was true suspense and a feeling that it mattered. To Lisbeth. To Blomkvist. And to us.
Take a peek at the trailer here. And if you've seen the movie, I really would like to know what you think. Did you love the movie? Do you think I'm crazy? Let me know!