Quite fun and better than most zombie games but ends up getting repetitive like other zombie games too. Also, there is no end goal in view. The only reason I played past level one was because I wanted to complete the game. However I am stopping now as the game is getting too repetitive.
Maybe you could add in companions (tired of playing alone on each stage) and survivors to rescue (instead of killing zombies again and again). Also, the voice actor is terrible. Your game could fare better without any voice acting.