Having read the second novel, I’m not surprised by the plot. But this is really a model of adaptation. The character work is even deeper in the series than it is in the books, the plot has been trimmed to its essentials, and ending the season with the supernatural creatures assault is more dramatically satisfying than the revelation of Bran’s (in the book less unambiguous) survival.
The series has been quite faithful to the novels so far; it will be interesting to see if they are as willing to sacrifice characters next season as George R.R. Martin has been.
"Game of Thrones" is every bit as much about the exercise of power as Caro’s monumental LBJ biography is. Not quite on that level, of course, but deeply considered and challenging.