It may sound weird, but I'm kind of looking forward to that, actually.
So, full disclosure, I'm a school librarian. I brought up my own kids telling them, "Read the book before you see the movie!" And now I've realized that was not good advice for the long term. (When kids might not read the book because they saw the movie, I believe that my advice still stands.)
Almost every time I read the book and then see the movie, I'm disappointed. I rarely like a movie more than I like the book it's based on. But, I've learned that seeing the movie (or the show, in this case) first, allows me to enjoy the film/series, and then, since I usually like the books even more, I get to add to that enjoyment through reading. And, especially in the case of GOT, anyone who watches and reads gets to enjoy two story lines.