Nabari no Ou's synopsis might seem like your typical shounen series; a boy main character who only wished for a peaceful life, but he somehow possessed a really great, inhuman power. That is like the basic setting for every shounen manga -- and with Naruto around, who needs another ninja series? We have had enough.
I've been following Nabari no Ou for more than two years - I liked the anime, so I started reading the manga. There were problems with scanlations - missing chapters and such, but somehow I managed to be up-to-date when chapter 49 was out. Since then, I've been eagerly checking out the new chapters every month.
Lastly, the characters need some work. Nabari no Ou wanted to be like Bleach so they put in a hole flock of characters - many of which they don't even use for anything interesting. They build up something about a character (Oda and Katou's relationship, Aizawa's 'secret' or Hattori's assistant) and then don't touch it any further. Personally, I would like to know how Oda and Katou hit it off afterwards, or see Aizawa use his EPIC secret in abttle at least more than once in 26 episodes. Even seemingly main characters end up just spectating or flouncing around, like Kumohira-sensei. At a certain point, the designs even started to get less interesting. However, the main characters they DO focus on are pretty captivating.