I must admit to a hefty bias coming into this: I do loves me some zombies. I get the feeling, reading other reviews, that people are generally tired of the shambling, hungry dead. I suppose the IF zombie over-saturation was before my time, then. I can barely find any of the stuff. Nevertheless, if you promise to keep an open mind concerning the children of Romero, I promise to be as objective as possible reviewing this little gem. Deal?
First off, this particular zombie apocalypse puts its emphasis squarely on the "apocalypse" part. The horror comes more from solitude, atmosphere, and despair than from "Oh crap that dead guy totally wants to eat me." The prose is tight, and efficient, never letting you forget that you are (almost) alone in a dead world, balancing on the brink of joining the uncountable tally of the dead.
But it's not as oppressive and fatalist as that sounds. Dally wisely (and expertly, I believe) straddles the line between levity and horror, never letting the game slip too far in either direction. Think Evil Dead 2, as opposed to its trilogy-neighbors.
So as a story, I dig Divis Mortis, and I hope you will too. As a game? It succeeded for me. The puzzles were intuitive, with no Insane Troll Logic. I only needed the thorough built-in hint system once, for a bit near the end. I knew what needed to be done, I just expected it to be more complicated than it was.
The bottom line: Play this game now, even if you're sick of zombies.