Production is already under way on Season 6 of HBO's hit series Game of Thrones, which will be the first season that isn't based on any of George R.R. Martin's books. While fans impatiently wait for the author to complete the last two books in his A Song of Fire and Ice series, many have also wondered if the show will run for seven seasons, one for each book, or if it will go even longer, given its massive popularity. During HBO's TCA press tour presentation, HBO president Michael Lombardo revealed that series creators/showrunners David Benioff and D.B. Weiss are currently planning to end the show after eight seasons.

"Seven seasons and out was never the case. The question is how much beyond (seven seasons) it will go. David and Dan are feeling there are two more years after Season 6, that's what we're looking at right now. We hope that they would change their mind, but that's how they are feeling now."

We reported in June that Game of Thrones is casting 14 new characters for Season 6, but we haven't heard about any cast members being added yet, even though production is already under way. It has already been confirmed that Bran Stark (Isaac Hempstead-Wright), who sat out all last season because his story had already caught up with the books, is coming back, along with Kristian Nairn as Hodor. When asked about a potential Game of Thrones prequel series, Michael Lombardo revealed he would be open to anything David Benioff and D.B. Weiss would suggest.

"We would be open to anything (Benioff and Weiss) want to do, there is enormous amount of storytelling in that world. The focus is on figuring out the next season."

Ever since the show debuted in 2010, Game of Thrones has been no stranger to controversy and criticism, with several vocal groups speaking out against the graphic content shown in the hit series. For instance, Game of Thrones Season 5 featured the rape of beloved character Sansa Stark (Sophie Turner) and a young child burned alive at the stake, just to name a few controversial moments. When asked to address this ongoing criticism, Michael Lombardo had this to say.

"This show has had violence from the first episode. I can't speak to any single person's particular taste, but I think the show is phenomenal. It went to 20 million viewers this year, it went up over 1 million viewers from the prior season. The show continues to grow dramatically. There are no two showrunners who are more careful about now overstepping what they think the line is-and everybody has their own line. [What they show] is critical to the storytelling."

In related news, it was also announced today that Game of Thrones Season 5 will be released on Digital HD on August 31, months before the Blu-ray and DVD arrives on March 15, 2016. The Digital HD release will also include a number of special features such as "An Introduction to Dorne," "Poisons of Westeros," "A Day in the Life" and "The Weapons of Dorne." Normally the Digital HD is released at the same time as the Blu-ray and DVD, just before the new season debuts on HBO.

As for the prequel series, it isn't known if this is even an idea David Benioff and D.B. Weiss are entertaining, but now we know that there is a specific end game in place, even though that certainly may change. Do you think 8 seasons is a long enough run for Game of Thrones? Or do you think it should run for years and years to come? Let us know what you think, and stay tuned for more on Game of Thrones as production continues.