Alot of the first season was from book 2 as well, remember a lot of the stuff in later books is happening at the same time as stuff in the earlier books, so obviously things will be a lot different on screen, hopefully nothing from books 6+7 will appear on screen before he finishes writing them for book
I'm liking it enough, but I preferred the first season - this season just seemed to throw to many characters at the screen. Not read the books so some of these characters seem alittle unneeded or half baked.
The last episode was really epic though.