Don't be fooled by Ninjatown's bright and colourful exterior. The fact is, when you get further into the game it starts to get pretty complex and requires some deep tactical thinking.
Basically, it's a 'tower defence' strategy game. Waves of demons try to travel through your town in order to get to your base on the other side, so in order to stop them you have to build various ninja huts by the roadside. As a demon passes a hut the ninjas inside emeerge for a scrap, but certain ninjas are only effective against certain enemies, and you have limited resources.
Ninjatown is a strange game because although its graphical style suggests it's aimed at younger gamers, its tactical gameplay really requires a lot of thought, especially in later levels. As a result we're not really sure if it'll be as successful as it perhaps should be. That said, anyone who buys it will be treated to a solid, if slightly generic, strategy game.