If survivors of the zombie apocalypse just waited long enough (and it wouldn't be all that long), wouldn't the zombies just decompose beyond the point of being a threat to humans?

First of all, their skin and muscle would wear away so they would start by losing mobility. Eventually their joints would start loosening and breaking apart. Most importantly, their brain would shrivel up into a raisin and cease functioning.

I'm surprised I've never really considered these things before.

I guess what all of it means is that in addition to having some kind of virus living in and controlling the brain, that virus would also need some kind of special properties that prevents decomposition completely. And, of course, it would have to infect all the tissues of the body before it is dead.

I like that all modern zombie stories have some kind of scientific explanation for how and why people become zombies, but it'd be great if they could also work on addressing why it is they never decompose.

(Side note: I also enjoy it most when characters know what the hell zombies are, as in Zombieland. It's annoying when the world in shows like The Walking Dead act like they've never heard the concept of the dead coming back to life and go out of their way never to use the word "zombie.")