What happens when Game of Thrones runs out of books to adapt?S

This is the biggest question everybody's wondering about. With George R.R. Martin toiling away on book six of A Song of Ice and Fire, what happens when the Game of Thrones TV show runs out of material to adapt? The good news: they're not going to slow down the TV show's hectic pace, or pad it out.

That's always been my biggest fear about Game of Thrones. Given the huge wealth of material in Martin's books, especially the later books, you could easily make each book into multiple seasons. Already, season three is just the first half of A Storm of Swords. I do not want to sit through three years of A Feast For Crows. In fact, I want the show to leave out some of the books' millions of subplots.

Luckily, the producers tell Entertainment Weekly that they are sensitive to this concern, and they do not want Thrones to last 10 seasons. Writes James Hibberd in EW's big cover story:

It's possible the producers, who know the broad strokes of Martin's ending for the story, might conclude the show before the last book is released. Not that anyone involved wants that to happen. "Ideally, the books come out first," Benioff says. "We don't want to become a show that outstays its welcome and tries to turn each book into three seasons. Part of what we love about these books, and this show, is this sense of momentum and building toward something. If we tried to turn this into a 10-season show we'd strangle the golden goose. There is a ticking clock here."

The EW article mentions one idea to allow the show to wait for Martin to publish his final volume, and end with a bang: turn the show's conclusion into a big-screen movie, which would have more lead time and a bigger budget. But HBO, understandably, doesn't really like that idea.