More than just its technical merit, which is very important in and of itself since so many novels shake and rattle along under poor structure, Maberry takes us deeper. We get inside the heads of several of the zombies (and therefore all of them, really) and realize that the human spirit is still inside, chained to an urge that they do not understand and have no power to control. They are not your usual zombies; they are more accurately described as "infected" than undead. And that is so much worse.
When you get to the ending you will say along with me, please, this one deserves a sequel. I want to know more about what happens.