I am a big fan of the tench series ever since the PS1 game came out, I love sneaking around and performing creative and brutal assignations and this aspect of the game does not disappoint. There are a number of ways of killing your enemy on the open ground and the game makes good use of surroundings to introduce a number more (I particularly like hanging down from a roof beam and breaking someone's neck).
A great emphasis is placed on stealth in this game, all of the levels are divided up into reasonably small sections which you have to cross to continue (dispatching everybody in each section is optional but does help you score). My main gripe with the game is what happens when you are spotted, you character will normally disappear in a puff of smoke/feathers and re-appear at the beginning of the section though all of the people you have killed stay dead. In previous games when spotted you just pulled out your sword and had to fight with the person who spotted you, (not stealthy but satisfying). However in this game you do not carry a sword as standard, swords can be carried but only as one of a maximum of 3 ninja items. If you are carrying a sword and are spotted you enter a poorly realised first person sword duel where you have to defend by turning the wii remote in the appropriate direction. The wii remote isn't very responsive and the whole system fells like it has been crowbarred in as an after thought. The limit of carrying 3 items means that carrying a sword at all times is not piratical.
Overall it is a good game if you are content to remain stealthy. The controls are a bit cumbersome but you quickly get used to them. Each section needs solving more or less like a very violent puzzle which is a good thing, but I do miss the option of being able to just hack and slash your way though.