The best horror games have incredible sound design. Dead Space is the example I'm thinking of right now, but Alien: Isolation, based on what's shown in the above developer diary, looks like it's pushing the boundaries and really attempting to integrate sound into the design in every way possible. Terrifying.
Alien: Isolation looks set to be a survival horror game in the literal sense of the term. You will attempt to survive and you will be horrified. With the focus being on stealth and hiding the the Alien, as opposed to mowing it down with a host of different weapons, sound appears to be a pretty big deal. It makes sense. When you're sitting cowering in the corner, you want to be listening for signs of the Alien so you can continue to hide.
It's just another sign that Creative Assembly are taking Alien: Isolation down a healthily awesome path. Cynicism fading. Slowly. I think I am ready to get excited about an Alien video game again.