I think that it depends opon the variant and the wirteing style, a bare
bones rules would be preferable to a badly writen naritive which has the
rules in it, on the other hand a sci-fi/fantasy based varient would seem
stale or flat without somekind of backround.  And when it comes to
background there is a very large gray area, becuase you could easily say
that why a piece was chosen to move the way it does is part of a bare bones
discription, but sometimes the reasoning is so complex it could qualify as
literature.

There is also a question of 'What is literature?' a common question is 'Is
a comicbook literature?' in this case it might be better as 'Is a
discription literature?' some would say yes, others no.  Certainly I would
always prefer a discrtiption into which some kind of tone or voice has been
put, but that is not the same as haveing something on the level of Ralph
Betza's Nemoroth, which gives you the feel and atmosphere of the game.  If
everyone could write on that level then we would have an impressive
colection of CVs and literature in one, and games that otherwise might have
been overlooked would be noticed and played.

I fear that I may have lost track of my point near the first or second line
but if I try and go back and change it this will make even less sense. 
Basicly what I'm saying is that a well writen back story or setting could
never hurt a discription, and in some cases it's absense would.  Also a
discription its self can have a certain literay flavor to it that makes it
easier to read and understand than a bare rules only format.  I think that
the most disireable form of a discription is first and formost the rules,
backround information on how the game came to be and why the pieces are the
way they are, and any story or such thing that goes with it, i.e. a game
claiming to be elven chess should say a bit about how the elves played the
game.  If the rules are mixed in with the other elements, like for example
as in Nemoroth it may also be a good idea to have them listed sepreately,
also as in Nemoroth, so that those that don't want to read the non rule
related elements don't have to, and those that want to quickly refrence a
rule can.

I know I rambled and I hope it made sense and was in some way helpful.