There's been a lot of zombie movies over the years, and Snyder seems to realize that. He tries to tackle some new things with zombies (he definitely has the budget to), smart zombies and zombie animals.
Movie looks good. The intro montage showing the start of the zombie attack is really impressive and the best planned part of the movie. Since this takes place out in the heat of Nevada, Snyder actually uses sunlight in his film, though it is still muted somewhat as is the director's wont. The zombie fighting is well done. It's especially fun to see the massive Bautista take down zombies with just a knife.
You get a sizable number of distinctive characters in this. The one who stands out the most is safe-cracker and comic relief Dieter (Matthias Schewighofer).
There are a lot of plot points you can question about this, especially the whole plan for the heist, but they weren't severe enough that they interrupted my just enjoying the film.
One thing that bugged me is that ending goes on a little too long past a good stopping point. It's not as long as Snyder's infamous epilogue to Justice League, but it feels inelegant.
Overall, Army of the Dead is a pretty entertaining zombie action flick. Nothing more, nothing less. Recommended.