Needs some fixin'
But really good game. As others have mentioned, meeting Mimi in hard mode breaks the game, but I played it on easy and got past her (did not hire).
The voice acting actually sounds really good, which is a nice surprise for a Flash game. The game itself is fun and challenging for the three levels you get on hard, and not really bad on easy. There's two things I want to mention, though:
First, the gun selection screen is too big and it takes to long to disappear. I realize it disappears when you fire, but if you can't see the zombie you won't shoot at it.
Second, reloading continues even if you switch weapons. That makes the long reload of the machinegun pointless, as you can just switch to something else for five seconds then switch back with no penalty.