It is based on the books that are a prequel to the LOTR trilogy. There will be no obtuse use of blood and gore, these are fantasy stories like LOTR and are aimed at most ages.
This movie has had more dramas than the Labor party....NO-ONE wanted to commit to direct, it has had more possible directors linked to it than you can throw a stick at. Jackson only ever wanted to produce it but had to step in to direct otherwise the entire project was going to be shelved.
I think the movie will be a big turkey after viewing the trailers but it does have a very big and nerdy fanbase that will flock to see it regardless becuase of the LOTR series.
Like the AC/DC pinball, the end result won't matter that much, because people are buying in to the franchise no matter what. If it's half decent it will do well.