George R.R. Martin’s epic fantasy A Song of Ice and Fire, currently incomplete at five volumes, is a book world rarity: a genre series that has broken through the walls of the fantasy/science fiction ghetto. It’s immensely popular among mainstream readers and critics and is garnering a lot of attention in academic circles, even before the final book in the series has been published.

Although concrete, reliable data is hard to come by, it seems fair to say that Ice and Fire has sold at least 15 million copies worldwide, though this is without sales from the most recently published volume, A Dance with Dragons. It has been widely reported that Dance sold more copies on its first day of availability than any other book in 2012, totaling 298,000 copies (170,000 in hardback; 110,000 as an e-book; and 18,000 as an audiobook). Total sales to date are unknown, or at least so far unpublished.

There are several good reasons for its astounding popularity. The world of Ice and Fire is epic in scope, peopled by dozens of carefully delineated characters, and written in wonderfully descriptive prose. A masterfully produced, written, and acted television adaptation of Martin’s universe doesn’t hurt, either, drawing in a multitude of readers who would otherwise have not been aware of the novels.

A Song of Ice and Fire also sits directly astride the e-book/paper book publishing chasm. Although this doesn’t entirely account for its widespread popularity, I suspect that embracing the new publishing technology has something to do with  …