Very neat, but rather short.
Don't even think about enabling English voices, you'll be disapointed. Looks like were done by the same group of Japanese actors.
On the bright side we have cutting edge graphics and satisfyiing gameplay, which is similar to Onimusha's although there are no puzzles (almost), the pace is faster, scale is bigger and the fighting system is deeper (if we are talking about Onimusha 1,2). Music is also worth mentioning, it is really great sometimes.
The plot seemed to me all mixed up, so let's not speak about it. :) The controls are pretty smooth. What else do you need to for a good game? Hope they hire real American actors for the US release next time.
Conclusion: not much of an innovation, but still a solid game for PS2.