Celebrim
Legend
To my mind this sort of begs the question (and this might be best as a separate topic, so forgive me and anyone should feel free to start one): what are the most recent fantasy fiction (from any media) influences on D&D?
It's almost easier to talk about D&D's influence on recent fantasy fiction, which to me, feels as pervasive as Tolkien's influence once was on fantasy. It used to be that in any fantasy novel, it was either based on Tolkien, or it was inspired by Tolkien, or it was a deliberate and conscious rejection of Tolkien. There is still some of that, but more often what I see is practically every new writer of speculative fiction comes to that profession through gaming, so that almost every story is either based on an RPG campaign, or it was inspired by an RPG campaign, or it has taken the lessons of an RPG campaign in world building and plotting and applied those to a new media. (I don't think we are to the point of conscious rejection of and rebellion from those tropes.)
But, if I could see a trend in where D&D is being pushed by the larger fantasy culture, it is more and more forward from the middle ages. This is often no more than drape changing, since almost nothing outside of Tolkien has actually been deeply ground in Medieval thought and literature, and mostly D&D has always struck me as a largely anachronistic setting with much of it culturally drawn from say the late 18th or early 19th century. This is most blatant for me in its approach to urban life, in how it imagines thieves, or pirates, or village life or really any specific of human culture. D&D has always been largely Dickensian with late medieval weaponry - the same sort of 'ancient' world that Disney fairy tales occur in, just with more warfare.
What more and more I see is giving up on any vestiges of a medieval reality, and firmly setting the game in the 19th century (and sometimes even, as in the case of Eberron, quite late into the 19th century and arguably even the early 20th). I think this happens because there are limits to how distantly removed from one's own time and culture one can imagine (without being a true scholar of that time, which usually involves learning dead languages). It's just easier to stretch ones imagination to possibly encompass Jane Austin or Dickens or Hugo or Dumas than it is to imagine the world of Beowulf or Chaucer or Dante (to say nothing of how few people have actually studied those things). And even if you can imagine it, fewer still want to or can empathize with a character from that culture. Throw in some boredom with the conventional settings, and you are seeing more and more fantasy set in the comparatively recent past.
I feel fairly safe in imagining that this trend will continue as even the 19th century becomes more and more difficult for people to imagine, and D&D gets gatling guns and explicit call outs to the stresses of the industrial revolution and other conflicts that went into shaping our prior culture (or maybe or just prior prior culture), and this will continue to influence D&D.