American Nightmare looks like Alan Wake, only rougher around the edges. The fictional Arizona town of Night Springs isn't nearly as interesting as the spooky wooded glades of Bright Falls, Washington, and it lacks the awe-inspiring weather effects. The darkness has indeed descended, but you won't find yourself positively engulfed in it like in the first game. The game mostly animates the same as Alan Wake, which is a very good thing. However, I recommend against inspecting anything too closely. At least Alan Wake's superlative lighting effects are still here to enjoy.
Sound design has also taken a bit of a hit as far as the big picture goes, but it's still mostly solid. Alan's voice (and physical) actor is still very entertaining to watch, and his doppelganger role as Mr. Scratch gives him a chance to ham it up in some delightfully creepy scenes. Yes, there's a new Old Gods of Asgard song involved in American Nightmare, and yes, it's a fun one. Your faithful narrator channels his inner Rod Serling, and does a pretty good job of it. The three new female characters bring the sound department down. When they aren't dull, they are annoying and throwaway. The soundtrack is atmospheric and intense, and the end credits song (Ed Harcourt's "Watching the Sun Come Up") is a perfect fit.