Awesome
Just plain great game, Ill try to explain my ratings.
Graphics: Everything looks great, from the zombies to the guns to the helicopters.
Style: Not the most original idea, but it was unique for what it is and nearly perfectly done. This is the first time ive seen the "Spend so and so hours doing something, survivors let you get more done"
Sound: Sound was good, although the M4 sounded a little fake. The blood splatters were a nice touch.
Violence: Great, althought I thought the chainsaw would produce a little more gore. I also enjoyed how you had different things, for example a headshot could produce the head snapping back, a big hole appearing in it, or the head just plain exploding.
Interactivity: This is your most flawed part. The aiming was a little strange, which was especially evident with the hunting rifle. Moving didnt really offer much, so if you make a sequel I would get rid of that, it would problably help with aiming. You also said that you could pick up weapons the zombies dropped, even thought I saw no way to get over the wall.
Humor: Great, but kinda ruined by the atmosphere. The daily notes were pretty nice, and I always laughed when a fat grandma with a knife in her head rushed at me, only to have her legs blown off and she does a frontflip XD
Overall, this is a great game, especially for a first flash, and I would love to see a sequel. Great idea, slightly flawed execution, although its a lot better than a lot of the crap out there. The main thing I would like to see improved are the aiming and the survivors AI. They pretty much sucked, even with 6 of em with you.