There is a reason why this movie is rated R so don't be surprise to see blood and bodies hacked off.
People before you start slandering the movie about it was too bloody and stuff check the ratings.
The only thing I found weak about the movie is probably the cg fx for the weapons, especially the shurikens. Other than that, this movie was flawless.
It was indeed a very good movie. It had a nice flow for the story line and it had awesome ninja fun (The type of fun that ninja enthusiast would enjoy).
This is by far one of the most successful ninja flick out there.