I picked it up today and played it for a little while. So far I'm enjoying it. It is a very different type of game so far. The game definitely relies on tension over action. I've had a couple tense moments and already a bit of frustration. You really have to pay attention to your surroundings or you'll get killed. For example, I was at a part to get around hunters. I shut off their generator and it took about 4 attempts until I noticed the hatch on the floor. In the next part where I finally meet the alien, he disappeared and while I was waiting for the tram, snuck up behind me and ripped me apart. I was dumbfounded.
The graphics are amazing but I definitely see some framerate issues and mouth movements aren't very fluid. But that so far hasn't detracted me from the game. You definitely feel in the Alien universe and the scenery design is amazing. I'll have more impressions as I get more into it.