The first couple hours of BioShock were very, very creepy. Of course, the second half of the game kinda lost all of its horror and just turned into a sci-fi shooter, but that didn't hurt the game at all.
It didn't blow me away, but it is better than anything they've written in a long, long time. The last three minutes are especially awesome. It feels like one of their older ballads with a touch of Orion and maybe a little ...And Justice For All.