I absolutely love this game, but man I wish there were multiple levels to it. I get the feeling of "Alright, I'm ready for the zombie apocalypse now!" then it's like, awwwwwwww.... man it's over.
I am really looking forward to the follow up to this. The nightmare sequence really caught me off guard the first time I saw it, considering how lighthearted the game is.
Giant Worm near the end was fun, the boss before that - the Tentacle thing was also fun.
Best Normal enemy was the green puddle zombies, I loved the zerg appeal - overall very very fun game in small doses.