Game of Thrones is going to get "pwned."

There, I said it -- and fans of George R.R. Martin's long-winded and epically tardy fantasy series can flame away. The version of GoT envisioned by Time Warner's (TWX) HBO enjoys undeniable popularity with the sci-fi/fantasy set. Yet the series suffers from one fatal flaw: its creator.

Author Martin published his first volume in the Game of Thrones series some 17 years ago. It took him nine years to complete the next two volumes ... then five more years to complete the fourth (A Feast for Crows) ... and then six more years before the critically panned A Dance With Dragons finally lumbered out of its cave in 2011.

Supposedly, two more volumes are in the works, and Martin plans to wrap up the series with them. But if he maintains his current plodding -- and even decelerating -- pace, it could take another 13 years before the text version of this saga flaps its way to conclusion. Meanwhile, at age 64, Martin is already no spring chicken -- which puts into question whether the series will ever conclude.

This, unfortunately, leaves the fate of HBO's franchise up in the air. Depending on the deal it's worked out with Martin, it has perhaps two -- or, if it's lucky and Martin types quickly -- three years of programming left before the revenue stream dries up. News Corp. (FOX) faces a similar dilemma, and in rather shorter order, as its HarperCollins subsidiary owns the distribution rights to the GoT books in the U.K. and Australia.

Longships on the horizon
Speaking of the U.K., there's an even more imminent threat to the GoT publishing/cable colossus, and it's already visible off the shores of Great Britain.

You see, capitalizing on the swords-and-sorcery success of GoT, the History Channel (owned by Disney (DIS 1.54%)/Hearst joint venture A&E) recently launched Vikings, a historical fantasy based on the exploits of certain Danish seafarers who terrorized Europe with their Middle Ages depredations.

Vikings became a huge success for A&E when it began airing in the U.S. in the month preceding GoT's Season 3 premiere on HBO. On Friday, Amazon.com (AMZN 1.30%) announced a deal in cooperation with MGM (MGM 0.99%) Television to bring the series to the U.K. and Germany via Amazon's local streaming subsidiary LOVEFiLM.

Result: Just as GoT begins winding down and going into hiatus next month -- and its fans begin going into withdrawal -- Amazon and MGM will move in to slake their thirst for ice and fire with an all-you-can-eat streamed offering of Vikings. Then, next year, Vikings will sail back in to take yet another ride on GoT's coattails.

Foolish final thought
It's at that point that things get really interesting for Time Warner, for News Corp. -- and for MGM, Disney, and Amazon as well. For the books Martin has written so far, next year's Season 4 will mark the penultimate. With only one more season certain to be produced, and with material written to support it, viewers will begin seeing the writing on the wall for long-in-the-tooth GoT.

At that point, viewers may realize that Vikings, not shackled to a lackadaisical author, and with several hundred years' worth of historical material to draw upon, has much more of a future ahead of it. The profits HBO & Co. have milked from GoT will begin to evaporate, just as the profits from A&E's franchise begin to roll in. (With the tide, of course.)

Then will the cry go forth: The king is dead! Long live the Jarl!