I find them overused. It's not completely the zombies themselves, it's the way they are used. It seems like they are always in the "realistic" apocalyptic scenario. They are usually done well, but this concept for zombies is getting old.
Why not more creative ways to use them? Why not some interesting traits? Like the Resident Evil zombies? Or zombies with powers? A half zombie half human superhero? Like Sid from Soul Eater.