I do think the maps are rather impressive (about as impressive as these poor damned graphics can get.) The Hadley's map (Tribute) is just great, and looks/feels exactly like Aliens. The amount of rooms and corridors there are, along with closeable (but not weldable) doors are truly a joy to fight through. So many little hallways and rooms, as you open your way to the Operations center and Medlab (where the Smartgun, Incinerator, etc.. are located) and the Aliens can pull the doors open behind you in truly scary fashion. There have been many times where I've backed myself into a corner and had Aliens swarming through vents, pulling open doors, and my tracker is going off all over the place. A lot of fun, honestly.
Pathfinding also seems a little better, though they still all line up to jump at the same points. If you catch them right, you can waste a whole spawns worth of enemies as they crawl up the same hole in the floor or whatever. An improvement, but still far from perfect. Far from AvP 2010's Alien movement, that's for damned sure.
I can't really make a call given this is $15. If it didn't have f**king WY, I'd say go for it if you already like the game.. but that does feel like a slap in the face, as many of you have said already. There's lots to keep people playing, but I'm still very much on the fence.