I like the word atmosphere, if it can be used in a wide enough sense (and not just mystery / horror atmosphere). I see it as a sort of holistic experience and something that is not possible to explain in any other way, other than playing the actual game.
Nowday when many reviewers divide game score into graphics/sound/etc, the "atmosphere" is taken into account in a way that it should. Seeing things like "the graphics are not good, but that does not matter becuase..." is very common. For my part, if the something does not matter, then I cannot see the worth in bringing it up as a negative point, yet this is very common. I think this is because it is common to focus on a very narrow aspects and then compare that to set preferences (for graphics: resolution, realism, effects, polygoncount, etc). Instead, a critic should only really focus on how it all comes together, and not single out specific features that is not really noticeable unless when scrutinized from a specialist viewpoint.
With both Penumbra and Amnesia we have heard this a lot, so it is extra annoying for me personally

This sort of focus on indivual aspects is probably also one of the things that are holdding back more artistic games, that have more holistic value. Instead there is a clear focus on each aspect of the game. Furthermore, I have heard from many studios that they are looking for people with spearhead knowledge in very narrow fields. I think this provides game where everyone is concerned with a specific aspect of a game, and nobody trying to maintain the big artistic picture.