Navagon: Here are some cut scenes from the game.
GG's own youtube of the game will give you a fairly good idea of the architecture. Although it seems to miss out some of my favourite bits.
As for other games with good architecture, one recent example is the colony city in Assault on Dark Athena and Bioshock, naturally.
OK, watched those two trailers/images and the architecture in it looks really good, might look even better at a higher res. Good cutscenes, too.
Gave me a impression that this could be a better game à la Cryostasis or Penumbra, if they gave it one or two more years. The environment is already there, just fill it with the suspense or horror, a slower gameplay; and they already had the cutscenes in a different mood.
But no... they decided to put cheap enemies in and make it a generic shooter with good looking buildings. And isn't that nurse from the Painkiller games? :p
Vivisector is from the makers of Cryostasis so might be a good game too, although it has beasts/monsters. I've never played El Matador, but it looks like a cheap version of Just Cause.