Well it seems that G.R.R. Martin has 'lost the plot' in his "A Song of Ice and Fire" cycle...
In the Acknowledgments at the end of the book Martin declares "This one was a bitch" presumably he means it was difficult to write... well it was an even bigger bitch to read to the end. What a downward trajectory this series has been on. The 1st book "A Game of Thrones" was excellent. A solid 'A' rating. The second book "A Clash of Kings" was very good, say an honest 'B'... but by book three the writer was really starting to lose his focus... introducing way too many sub-plots and getting bogged down with far too many minor characters to keep track of, so "A Storm of Swords" deserves a 'C' at best. Five years later... he gives us 978 pages of fodder. Brutal. The plot isn't progressing anymore... its going in tiny circles... nowhere fast. Get a grip Martin... we read the first book because it was fast paced and exciting... the exact opposite of the incredibly slow and boring "A Feast For Crows" rating: D-

I only finished this book because I still had some interest in the character of Arya Stark... I might have saved myself the time and misery of reading the rest of it... and simply skipped straight to the chapters concerning that last remaining character of interest... even Tyrion (the second best character) is basically missing in action. Brutal. I won't bother with any more Martin material... he's sold out...gone the way of the serial writer... writing pulp in nothing more than a lame money making vehicle a la Jordan's "Wheel of Time"

It's been two years since the land of Westeros was rocked by the deaths of Jon Arryn and Robert Barathon, and the realm has been split into several factions. Battles are being fought everywhere, and for every rebellion put down a new one springs up. Thus a Feast for Crows is aptly named; the crows feast and feast well. Alas, the readers do not. Due to its size, Feast has been split into two novels that take place at the same time, and a lot of key characters are left out of the 4th book. In their place are a lot of minor characters, who in truth don't seem important enough to focus whole chapters on. The editors thought so too and relayed that message to Martin, but the author felt they were important enough to include. Still, I would rather the Greyjoy chapters been axed and the main character PoVs expanded, especially since I was dissapointed in Sansa and Jaime's chapters. But that's just my opinion.
While not as good as the first three books, it's certainly entertaining to read AFfC. So if you haven't already, go and buy it. The crows await.

In the 4th book of A Song of Fire and Ice, Martin picks up right where he left 5 years ago, at the same high level and quality. The pace is good, not too fast or too slow, and each chapter has its own power and depth. Again we see a wide caleidoscopic view throught many characters and this time several temporary new viewpoints are added which enrich the scope of the story, because the persons from which the story is viewed in the chapters is limited and now we see more of all the events that are happening in Westeros.
And again those events are quite dramatic with many new unexpected twists. That's what A Song of Ice and Fire makes such a great fantasy series: Martin manages to truely create a quite unpredictable story, while many others often follow too predictable paths. Martin certainly did a fine job in the development of Cersei through the course of events in the story.
One warning though: to be able to finish some storylines in this book, Martin has put the new events in the North and about Daenerys in book 5 when he noticed his novel got too large to publish in one novel, so the people who are desperately waiting for new events there will have to wait, but not again 5 years, since Martin has written half of book 5 already.
In this book Martin starts a few new developments that make me wonder a bit about the timeline of the story. The current pace seems it hard for those developments to finish in time, so I'm interested in how this will be resolved in a satisfactory way. But I have faith in George R. R. Martin's ability to do so.
With this new book A Song of Ice and Fire remains one of the best fantasy series around, even after a wait of 5 years. It certainly was worth it.