George R.R. Martin has spoken at length about his complicated feelings towards fanfiction. He doesn’t much like the name, and he also feels that in the age of the internet there is too much public attention on fans writing about their favorite characters. He doesn’t approve of people playing in the ASOIAF sandbox particularly, because as he puts it: “No one gets to abuse the people of Westeros but me.”
In a recent interview with the Sydney Morning Herald, he also took the time to talk about the future of Westeros—as in, the future after he’s no longer around to write the books himself. He as decided that he doesn’t want anyone continuing the story in his absence, in the style of Ian Fleming or Robert Ludlum, because he’s too concerned about the quality of the stories. As he said:
“…history has shown us is eventually these literary rights pass to grandchildren or collateral descendants, or people who didn’t actually know the writer and don’t care about his wishes. It’s just a cash cow to them. And then we get abominations, to my mind, like Scarlett, the Gone with the Wind sequel.”
He specifically praised the Tolkien estate for taking care of J.R.R. Tolkien’s works, as he assumes that there are people hungry to use those worlds, and he feels it would diminish Tolkien’s legacy. “I hope I never see Sauron Strikes Back written by some third rate writer who leaps at the opportunity.”
His answers to the interviewer’s questions are very much in line with what he’s said in the past—that he thinks writers need to create their own worlds and characters—and with the possibility that HBO may reveal how Game of Thrones ends before the books can do so, it would seem that there is a very real possibility of his worlds striving to exist beyond their author.