Just started reading the books, i am already hooked, there are some different things in the book than what occurs on the TV show. I must admit for any non-book reader, give this a go.
The TV show fails hard in depicting the "living world" of ASOIAF. Every character has tons of relatives and backstories that all play into the story somehow, generations of families feuding and intermarrying (enjoy all the Lannister cousin fucking) that adds a ton of depth, that the show understandably cannot get into at all.
Also if you enjoy military history at all, the books spend a good deal of time talking about military strategy, where you get to sit in on discussions and debates of the political and maneuver decisions behind major players in the war of the five kings, (almost heh) always culminating in bad ass battle scenes that turn gritty and gory as fuck with thousands of troops, that the show simply cannot do even at its best attempts like Battle of Blackwater.
That's all on top of the fantastic dialogue, twists, and memorable characters you get in the TV show. Its good, yeah.