Somehow I missed this thread before...
Although each book has great characters and memorable moments, A Game of Thrones is my favorite. Imp and Brian pretty much said it all... It is the foundation. It sets the pace. It is unapologetically different from Tolkien. It is low magic. It features an epic political struggle.
I love all of that, but when Jaime pushed Bran and Ilyn went for Eddard, I knew all bets were off. The traditional and well used formula was no longer in effect. And I know would not have liked it as much if I was thirty years younger. The themes are different from The Belgariad and Riftwar.
The introduction of Jaime's POV in ASOS and the explanations of his actions was the biggest moment of ASOS for me.. not Edmure's wedding nor Joffrey's. I will say that those were monumental chapters... Robb and Joffrey! But it was Jaime's realization that he was the villain of the story and his subsequent resolution to become the hero that captivated me. He is my favorite character. He's still not a hero, nor probably ever will be... but he's irresistably intriguing. He, alone, makes ASOS the second best book.
A Clash of Kings features Tyrion as the central character. Yes, Jon and Dany are important, but they're on the periphery and I figure they'll get to KL or the main action eventually. Tyrion runs the government and prepares against enemies within and without the capital... and finally, he commands the defense against Stannis. Plus, Catelyn's last chapter really begins the Jaime story... and it may be my favorite chapter in the series.
The fourth best is A Feast for Crows. It's not that the story stalled as much as people say, it's the fact that it only had one of my two favorite characters... Tyrion was omitted. And this was compounded by a plethora of new POVs in Dorne, the Iron Islands, and of Cersei. It is not that I disliked them, but it was a new investment of mental, emotional, and psychological energy that I was not ready to give. I knew the level of commitment for the first three books and I expected only one or two new POVs for AFFC... and I got at least seven, I think. Aeron, Areo, Arianne, Asha, Brienne, Cersei, and Victarion. But I must say that my second favorite chapter in the books is Brienne's fifth in AFFC... that is where Septon Meribald talks of broken men, outlaws and war. Powerful stuff.
The last book on my list is the latest book in the series. Even more new POVs and reintroductions of old POVs that have been missing since ACOK and ASOS. I fully believe it is the sheer number of POVs that slows down the story... It takes so long to get back to characters that it is impossible for me to keep it all straight. I'm excited about Connington and BFS getting POVs.
And yet, I have to say that the multiple references to bestiality was disturbing. Chiswyck's story of the Mountain's rape of the tavern girl in ACOK was disturbing too, but it was there to display the rapacity, depravity, and brutality of the Mountain and his men. But the bestiality did not accomplish this for Varamyr nor for Ramsay. I, for one, already detested Ramsay as a rapist, liar, murderer, torturer, thief, and complete sociopath... bestiality was unecessary. And in the case of Varamyr, he was supposed to be receiving sympathy from the readers and BAM! there was this mention of wolf mating.... I felt it was meant to be more titillating than enhancement of the character. I like dark fantasy, but not bestiality.