Most of the time I find that when I mention Nabari no O, a majority of people have never heard of it. Those who have usually don't watch it, because it does have some plot similarities to the Naruto series.
However, despite the fact that both are ninja anime, when you get down to it they are nothing alike.
Nabari no O is dramatic and each episode has significance. This show will make you laugh, cry, and yearn for more.
The plot has several twists and turns. You can almost never predict what is going to happen next.
This show is, and will always be, one of my personal favorites.