On the plus side, at this point the thread faggots can't do much more damage (without it being blatant, that is). Probably half of the storylines have passed the books at this point, and the other half are damn close.
I don't think we'll get to the point where the threads merge, as the spoiler thread is basically "book readers talk about the show" and this is the non-book reader equivalent. But it's getting to the point where the worst you'll hear is stuff that just expounds on the universe like the Valyrian weapons list that Tuco posted. It doesn't spoil anything and just gives you more info, but it's information you'd only get from non-show sources.
Actually, was just thinking about it and there's a lot of talk in the spoiler thread about storylines long passed that got cut. People still talk about "just wait until soandso happens!" despite all evidence being that it'll never be in the show.