Out of morbid curiousity, I watched this movie. It is the american adaptation of Death Note. The series of Japanese live action movies I purchased years ago. And greatly enjoyed.
This movie? This movie suffers all of the problems with an americanization of a foreign property. They went for more gore and introduced plenty of profanity. It gives the impression that the producer and director felt they had to out-do the original property to make it palatable to western audiences. That they were somehow above what they were working on. And honestly. I found that pretty insulting.
My recommendation? Skip it. It's not worth your time.
If you can find Death Note, Death Note: The Last Name, and L: Save The World. All by adapted in the US by Viz Media. Grab them! They will give you much more enjoyable experience.