"Irrational Games wanted to give the genre a kick in the pants much the same way we did to the first person shooter genre with System Shock 2. Too many survival horror games adhere to the same formula. You're running around an enclosed space and every once in a while, some scary thing jumps out at you and says boo. We wanted to challenge that."
Read the interview here.
Also, TheLost website has another ring (Gehenna) opened for inspection.