It is one of the most cinematographically stunning films I've ever seen. The director's use of colour in alternate storylines is something subtle that really gives the movie tremendous visual depth. Some of the fight scenes go beyond being action and become more like art. It's a mind blowing visual treat.
That said, the plot is something that would be far more accessible to the movie's intended audience. I had friends say it was 'stupid', but people need to bare in mind that this movie reflects a Chinese mythology. Flying ninjas seem cheesy to us because our Western culture mock and satirises the Asian mythology so often, but to a Chinese audience, it would be every bit as compelling as The Passion of the Christ was to Christian audiences.
Whilst I did find the storyline a little tedious at points, it was overall very well done. As I said, you see it for the tremendous visual aspects, but the storyline in no way detracts from the viewer's experience.
A solid 4.5 stars