Its Ninja Gaiden without the controller bashing, punch your mom difficulty.
Action packed you'll never have a dull moment in the game there is something to kill all the time. I really like the part where you had to press a button at the right time to perform a certain action during the cutscene it makes you feel that you were involved with the cut-scene.
Boss battles were fun as hell from huge monsters to chasing a boss through the highway you'll never get bored when fighting the big bad boss. It never felt unfair but you'll receive enough of challenge to feel you accomplished something and not just breezed through the game.
Upgradeable weapons was a nice affect I wish you had more weapons to play with but it was still cool overall because during mid combo you can actually switch out your weapons. So you can start out with your lightest sword and follow up with an uppercut with your heaviest sword mid-swing only to bring down with your medium sized blades, freaking cool.
Ninja Blade also had extra content so you can track your score with each mission and compare to see how did online. Changing your costume was pretty fun to but didn't add any powers so it was more for show.
All in all Ninja Blade was a good game I encourage you to rent it before you fork over your hard earned $59.99 to see if you like or just play the demo but I promise you won't be bored with this game.