A while ago there was a sub-discussion in a thread about books ads on Gaiaregarding fantasy creatures as protagonists. (It spun off from the fact that there was an ad for yet another vampire book.) Someone asked if we knew of any books with zombies as the protagonists.
Well, I can't say the zombies are the protagonists, but they are a driving force in the book The Forest of Hands and Teeth by Carrie Ryan. Mary lives in a village in the Forest, where only constant vigilance at maintaining the fences keeps the Unconsecrated out. Warning: I did not find the ending completely happy.