Also, I wanna talk a bit about dead space... The first one was the most scary but after EA decided to milk the **** out of it, it had lost its scariness...
I really felt like Dead Space 2 improved on the horror aspect so much compared to DS1.
In DS1 I could always predict when a jump scare was going to happen and I didn't really get scared by the atmosphere, DS2 was completly different for me.
There was the introduction of new enemies every now and then that kept the horror fresh, each with a slightly twisted characteristic, then there also was more of a psychological horror than the first one with the dead wife, and I liked how the horror was no longer in a distant ship but now in your home area.
Forbidden Siren
I haven't played it personally but the one of the developers also worked on SIlent Hill and the gameplay I saw of it looked great. It had those good morbid monsters you look for in horror games.
I would say my favorite horror game is Bioshock, although I haven't played many other horror games and mostly read things about them or watched videos for lack of money/console.
I would say it's my favorite horror game because it has the world made in a way where at first appearance everyone looks insane, until you realize the reason for their lifestyle, except for the main bosses, which through their audio logs, sound pretty much just insane.
But then the little audio clips from the bosses make the game even more interesting because it adds to the atmosphere even though their work is mostly contained into one area.
I have heard Condemned: Criminal Origins is a good game, and bought it, but haven't played it yet.
F.E.A.R. I have played and liked but I feel like it is too action based to really be terrifying, like I'm mostly doing cool kill shots and ignoring the little things that are supposed to make you uneasy.
Amnesia I found to have way too easy of AI to really make formidable opponents and make the environment scary. The atmosphere was pretty good otherwise, but the AI is just so bad that it made it funny.
Right now I'm looking foward to trying Condemned and The Evil Within.