very addictive!
good: the paths of the guards were not predetermined, making for tense gameplay. the abilities giving you the edge in a tough situation.
bad: the in-game music didn't seem to fit with the setting, i heard trucks; cars; and a seagull, what's a seagull doing in a warehouse?
improvements: i do think that you should be able to kill guards when their backs are turned, even if it meant that it would cause more panic. I would like to see some sort of distraction system, like if you could knock over things or blow stuff up, in order to divert attention for a little while.
oh, and more levels =)