Arya Stark (Maisie Williams) and Sandor "The Hound" Clagane (Rory McCann)
HBO Arya Stark (Maisie Williams) and Sandor "The Hound" Clagane (Rory McCann)

UPDATE: "Game of Thrones" is a major ratings coup for HBO (see Season Four premiere numbers below). So it's a no-brainer that the premium cabler would renew the series for a fifth and sixth season, which it announced today.

Fans of the fantasy series can rest assured they'll be seeing new GOT episodes into at least 2016.

EARLIER: The Season Four premiere of "Game of Thrones" got off to a big start April 6, nabbing HBO's largest viewership since the "Sopranos" finale.

Roughly 6.6 million tuned in for the inaugural episode to the new season. Meanwhile, 11.9 watched the "Sopranos" closer in 2007. The previous highmark for GOT was 5.5 million for an episode midway through Season 3.

Below, our review of the new season:

"Game of Thrones" is more realistic history than genre fantasy. 

In the run-up to the launch of HBO's "Game of Thrones" Season Four, the great British TV critic Clive James has been catching up on DVD boxed sets -- and enjoying it, despite some confusion. "I didn't quite catch the name of the place from which the dragon's eggs were beyond," he wrote in The Telegraph, "but I instantly made my plans to jump ship if the dragons ever hatched."

James happily didn't follow through on these plans, and has continued to enjoy the show, but his initial error of seeing "Game of Thrones" primarily as a fantasy series is still too widely shared. Some critics have suggested disapprovingly that elements of the mores of Westeros could simply be adjusted by George R.R. Martin, author of the five source volumes (to date) of the military and political epic "A Song of Ice and Fire," because after all these are just grim fairy tales, and can take on any shape or form their creator prefers.

It seems obvious that the fantasy elements of "GoT" are mostly incidental, operatic rhetorical flourishes used to externalize some elements of the human drama. The dragons that grow larger in each book, and in each TV season, work well as giant metaphors for the growth of the spirit of their mistress, Emilia Clarke's increasingly regal Daenerys Targaryen, royalist claimant to the bitterly contested throne of Westeros. At heart, "Ice and Fire" is a realistic dramatic novel, patterned on British history.

This is not news. From the beginning, many of the show's keenest admirers have argued that the books would read almost as well with all the Wights and Walkers surgically removed. And new Kindle publication by Ed West, previewed in "The Spectator," cites chapter and verse to show how closely "Ice and Fire" adheres to the events of historical upheavals such as the War of the Roses. Martin himself advises readers looking for more of the same to jump straight into historical fiction, naming the multi-volume medieval epic "The Accursed Kings," by the French novelist Maurice Druon, as a key influence.

"Ice and Fire," and therefore "Game of Thrones," are realistic in the way that matters most: their depiction of human behavior. Setting the stories in a world based fundamentally in historical fact can be seen as a form of authenticity insurance, a built-in check on the natural human inclination toward wishful thinking. Hard to avoid, perhaps, in a genre that often falls back on elves and trolls.

The visual presentation of sex and violence on "GoT" has often veered toward pure spectacle.  No use trying to deny it. In the very first episode of the new season, the camera once again gazes lasciviously at naked King's Landing prostitutes who resemble Sports Illustrated swimsuit models. No aesthetic of realism is being served there. But in some of the series' most notorious sequences, such as those depicting King Joffrey's violent debaucheries, it was.