This is pretty good. It kept me busy for a better part of my day (maybe I should have been doing something productive, but I found this to be a much better use of my time), and I really enjoyed it. I like the visuals, and the gameplay has a good balance between being simple enough to pick up quickly and complicated enough to have to really think about what you're doing and plan ahead. My only criticism would be that there isn't much replay value to the game, other than if you want to do it on higher difficulties. I also am slightly irked at the fact that you have an overrun tile that you can't clear out completely once you cure the zombie virus. Overall, though, it's a pretty nice and polished game, and I would definitely recommend it to people who like this type of game.