An entire season per book?!
Okay, maybe once you hit book 4 or 5 that MIGHT be justified, but particularly books 1 and 2 do not need THAT much screen time to adapt. People often forget the difference in mediums, what might take longer to establish through description and such in a book can often be shown visually in a film or such far more quickly.
I'm just worried, this smells slightly of Peter Jackson's Hobbit (for the record, I thought film 1 was great, but 2 and 3 had good moments but a lot of bullshit) as in this just means some stuff will be drawn out and a bunch of unnecessary original material will be stuffed in to justify the runtime.
I doubt this will measure up to the films (for all their faults, most people still see them as a solid adaptation) even if it becomes a more "accurate" adaptation (similarly, I do have criticisms of Kubrick's The Shining for its deviations from the book, but it's still far better than the "more accurate" TV series version) . Hell, good luck topping that classic John Williams score.
If HBO were to do a series set in the universe, I'd much rather see a new group of adult characters out exploring the world and dealing with threats rather than revisiting the exact same story in the exact same location.