 A big reveal happened in Episode 1. At the end of the premiere, just before Viserys' names were near as his official heir to the Iron Throne, the King tells his daughter a secret that has been passed on from one Targaryen to another for centuries. He says that Aegon the Conqueror, more or less the founder of Westeros, had a dream that a terrible winter would come and that the only way to defeat it was with the Westeros united under a Targaryen on the throne. Viserys then says that Aegon called his dream a Song of Ice and Fire. Did you point at the screen like that Leo meme when he said that? A Song of Ice and Fire is the title of Martin's series. Now we know, officially, what it means. That's not in any of the books, but it did come from Martin himself, according to an interview with the showrunners, her insider. And because this wasn't a part of the book, that means the part where Viserys slips up and accidentally tells Allicent wasn't either.