It's meant to be. The book is quite dark - it deals with instituionalised rape, sexualised violence and serial murder. The original Swedish-language film doesn't really admit that it's dark; it flirts with the prospect, but always holds its characters back. But as David Fincher proved with SE7EN, he's not afraid to push his characters over the edge and see what happens. So I think this film will be very dark indeed (why else would they tag it "the feel-bad movie of Christmas"?).As ever Craig looks great, but the music was a bit jarring for me
The song itself is a cover of Led Zeppelin's Immigrant Song (which is about the Vikings crossing the Atlantic) by Karen O of the Yeah Yeah Yeahs and Trent Renzor, of Nine Inch Nails fame and who also picked up the Oscar for best score when working with Fincher on THE SOCIAL NETOWRK. Take on its own, the song isn't really anything more than a Led Zeppelin cover with an industrial slant, but I think it perfectly matches the visuals in the trailer. Especially the line "Valhalla, I am coming".