DevelopmentThe game was canceled after 2 years of development only to be given a 10 month reprieve. In an article by developer Kevin Fuller, he admits that his team did borrow some ideas from Bioshock such as the audio recordings.
German versionIn the German version, gore effects were removed and blood effects were toned down. Both differences only apply to human enemies. A detailed list of changes can be found on schnittberichte.com (German).
ReferencesIn the final level, after you get the last upgrade for the TMD, you can smash a vent in that very room, go down a ladder, and you'll find yourself at a narrow room, at the end of which there's a crack in the wall that lets in a bright light, and has a large donkey wheel wedged in. This is a clear wink at fans of the TV show Lost: A wheel, very much like this one down to the room it's located in and the way to access it, played a major part in the ending of season 4.
The entire thing can be seen in this video: http://www.youtube.com/watch?v=VdWxZy8NlBs
In the Xbox 360 version of the game you get an achievement for finding this.