Derren said:
It depends on how you define recently. During the cold war era heroes were mostly perfect individuals who battle against evil. Just look at some media from that time. After the 80s the heroes in the culture became gradually less perfect. Perfect heroes were regarded as boring and they needed a dark secret to become interesting again.
I disagree with you about the "perfect heroes" during the cold war, but agree about the boringness of that kind of characters. This doesn't mean I oppose heroes or heroism, quite the opposite. In my opinion, a character without any dark shades, moral doubts, weak spots etc. cheapens the value of goodness; where is the virtue, if you are never tempted?
(Of course, people have all too often gone overboard in the other direction; for example, the so-called Iron Age superheroes who are just as ridiculous and much less interesting or appealing as their too-shiny predecessors.)
Also look at the differences between the old Battlestar Galactica and the new one.
The chief difference there is that the nBSG has production values and acting worlds above the original series, and actually looks at how the survivors of an apocalypse might react.
And while I haven't seen the latest Bond movie I heard that Bond also got back to his "roots" as government assasine and not gentlemen spy.
Bond in the books (and in the few earliest movies) is a sexist, snobbish and quite brutal bastard, whose job includes killing very often. (That's the whole point of his 007 classification; he is willing to, capable and licensed to kill.)
In the past paladins were shining knights and compared to today not many questioned how paladins have to behave themselves.
I really doubt that; stories about Lawful Stupid, stick-up-their-ahem paladins are as old as the class. In the older editions, however, the paladin's code was spelled out in more depth (or at least bredth) than in 3.*, which may have helped with the corner cases.
But today more and more players are dissatisfied with paladins because they are too restricting with their "no evil" code.
In my experience, people are dissatisfied with paladins since the players and GMs tend to have very different opinions of where, exactly, the paladin's limits are. (That, and clerics tend to be mechanically better as spellcasting holy warriors anyway.) Furthermore, the inflexibility of paladin's code brings out the worst in many gamers, leading to never-ending threads about orc babies etc.
And saying that design decisions in D&D are not made to give what the people currently want (in this case dark heroes) is nonsense. D&D is still a product that has to sell so it gets changed to what the people want. The evolution of the drow a probably the best example of this.
I'm not denying that people now like and want dark(er) heroes and themes; what I disagreed with was your implication that this is somehow a new issue (or a sign of shallowness). As for the drow, they are if anything even nastier these days. It's just that a lot of people want to play the non-NE or CE outlier individuals.
Kahuna Burger said:
The only backstory available to a core class? Not in my game.
Good thing that there are going to be at least shadow and fey pacts as well, isn't it?
Kobu said:
I have a feeling that someone at WotC is really into the Harry Dresden books. Wizardly implements, the Hellfire Warlock, and now fey and demonic pacts all ripped right from the pages of the Dresden Files.
Well, those are pretty good books.

And, as you yourself mentioned, they are not new ideas by any means, and have a basis in folklore and myth; if anything, we should wonder why a thing like a wizard's staff has been portrayed as little more than a grenade launcher in D&D for years?