I think it's definitely a modernized take on fantasy. I have never liked the genre and yet I get into this. There's good and bad within the good and bad. "Good" guys make really terrible decisions. Some of the bad look for a measure of redemption but they can never be fully forgiven. Also I like the sudden chaos of it, with key characters being killed off unexpectedly.
That's what the younger fantasy fans will tell you too when they contrast series like GoT with slightly older series like The Wheel of Time. I disagree. Although that trend is
relatively true for fantasy in general, inasmuch as the protagonists are almost always dark or anti-heros now, such protagonists aren't new, just more dominant. Even one of my favorite childhood fantasy books, little more than a D&D role-playing game in novel form, focused on a good guy gone bad who still often did good things.
P.s. I think one of the reasons the books are more appealing to non- fantasy fans is due to the relative absence of some magic system in his world. But even that's not unique to Martin. He's just near one of the ends of the spectrum vis a vis magic (it exists, but isn't used frequently, and the rules behind the magical system aren't developed or dwelled on at all).
The Jon Snow theory is a popular one.
As for the ending, I will feel a bit cheated if it ends as Nelson suggests. I agree that the story is at its heart a well-written fantasy series, but what set it apart was the story of political intrigue that overlays it. I want the winner to win because they were more cunning than the rest, not because they team up and have Dragons. I will feel a bit cheated if that's the case.
I hear you, but I'm telling you to prepare yourself.
Fwiw, I'm not saying there will be three people who win the throne by teaming up with three dragons. That's unlikely. But the series is not called the Game of Thrones, only the first book is, because winning the throne isn't the overarching plotline. The series is called The Song of Ice & Fire---the battle with the Others, which Danny and her two-dragon comrades will wage to save the world or some such thing.
Bit of trivia---the series was supposed to be only 5 books long originally. Martin was going to write about the disruptions to the realm and the Stark family wrought by King Robert's death in the first two or three books. The latter books were then supposed to fast forward to a different starting point so that the Stark kids were older. Because the overarching story was never about the game of thrones; Martin just lost control of his series and couldn't wrap up his own plotlines quickly enough. The story was instead supposed to be about the Stark kids & Danny's fight with the Others. Everything else is just a distraction (for the characters at least, if not us).