It's the third iteration of the Clash of Ninja series in the United States, but it's not Gekitou Ninja Taisen 3. The game's development is a little tricky to explain, because unlike previous releases, this isn't a simple localization. Figuring out if it's worth your money essentially comes down to whether or not you've already bought one of the previous games, or if you're satisfied with tacked-on motion controls and a few new faces in the Character Select Screen. Annual iterations, roster updates, and minimal improvements over its predecessor? I'm surprised '08 wasn't slapped on the cover, to be honest.
It's a bit strange that the Clash of Ninja series reminds me more of Madden NFL than Smash Bros.