The night is dark and full of terrors
If you do happen to fit both those molds, you're going to absolutely adore this game, like I did. But it's a shame there's no option to dumb down the mechanics so non-gamers can get the story without having to worry about attribute points, weapon loadouts and skill trees.
It may be little more than a glorified fan fiction, but it's a fan fiction written by true fans, and it fits in perfectly with the existing story. I'm not sure what Martin's official decree is on this particular subject, but I know I'm going to be thinking of Mors and Alester the next time I'm watching the show or reading one of the books. For me, their story has become canon.
Don't expect a happy ending. GoT pulls absolutely no punches. The protagonists are tortured, important characters are butchered and raped, and any mundane battle can end in one of several brutal execution animations. You'll even get to spend some time at Chataya's, the finest whorehouse in King's Landing.
Some technical issues aside (especially toward the end), it's a solid experience. It's just not for everyone. But if you revel in the brutality, self-deprecation and masochism of the series, then you will positively love this game. If you can get past the archaic mechanics, GoT can provide yet another way to steep yourself in the wonderful, dark world of A Song of Ice and Fire.
No doubt Maester Martin approves.