Because I've read the books I'm not too afraid of spoilers myself. However people I might be playing with won't know much, besides probably what the HBO series showed.

I'm sure there won't give any blatant spoilers, but I wouldn't want any special events popping up on a card text or something. (I could give examples, but I don't want to spoil anything for those who haven't read that far yet...)

I, for one, who played "A Game of Thrones : The Boardgame" before watching the HBO series : )

And I don't think playing board game will result in spoiler anything in the novel.

While I watching series, it's still difficult to guess what will happen next.
Just don't let's your guard down and spoil the player by yourself, that's the only thing you should worry about, ha ha XD

 I haven't played the 1st edition (yet), but a friend of mine owns it and I read the Manual and looked at all the cards.
I think that if someone watched the 1st season of the HBO series and/or read the first book he won't be spoiled. Some unknown characters will appear in the cards, but that's it.

However, I do think it spoils for someone that hasn't read the first book entirely or watched completely the first season of the TV series, because the game focuses of the "Five Kings War", and this war starts near the end of the first book/season.

PS: I did my best not to spoil anything important, forgive me if in any way I did so :P

There are a few minor spoilers on the House Cards: two characters wear crowns (end of the first book spoiler) and one character's card has the Wall as the background (end of third book spoiler). Also rulebook quotes a dialog from the second book, but it spoils nothing new that we don't know by the end of the third book.

In my opinion, the game has no spoilers.

I was a bit worried about that too (I've just read book 1 and 2), but the cards and rules really don't talk about the plot, beyond explaining that this is a land engaged in warfare between powerful houses.

In fact, two people who die in the first book are present as playable character cards, so that kind of tells you the way they've set it up.

AlexiusK said:

But you see, those aren't spoilers to someone who doesn't know. Rather, it is you who have spoiled these things by pointing them out, not the board game, as I personally would have never noticed.

 If you have read the first book or seen the first season of the show (and really, who hasn't if you are playing this game?) its a spoiler free game. There are a good deal of unknown characters but other than that, its all good. 

In my group three of the players had only seen the show and they did not seem concerned with the content of the game.

I completely agree with the comments about being spoiler free, for most people. However, If you are 100% new to GoT and starting off with the board before watching the TV series or reading the first book, then yes you could have some spoilers, but then again. How many people are going to start off with the board game before know more about it?

I would say if you are going to play the game, I would try to catch up by watching the 1st season of GoT then it will also give you a better grasp of the game as well.

You shouldn't be worried about the game as it doesn't give anything away if you don't know what you have to look for.

You should be more concerned when having big fans of the books in a game cause they tend to spoil even if they don't mean to.