The actual rating would be something like 3.4 stars. To set it apart from the previous two books, I rated this three.
I had my favourite Fantasy moment so far in this book, with Bran, the Reeds, and Samwell.
I also had new reason to confirm the author as Lord of the Hints.
And I also had just too much blood, and gore, and gruesomeness. It isn't that I felt disgusted or sick or disturbed. I just got bored.
Still, after a certain infamous wedding I had a reading streak and quite some good moments, including a second wedding gone awry (which reassured me that my view on weddings is healthy: just stay away). But in the end, I found myself stumbling again, and felt a little, well, cheated by the author in pulling a "trick" or two that would send roleplayers everywhere jumping in their dungeon master's face.

Only read the following hidden passage if you have read the whole book already. You are warned.
I am sure Arya will be quite pleased, should she ever find out that she dragged her mother's corpse ashore after a few days of rotting in water with her direwolf's help so that Lord Beric and His Merry Men could find and resurrect her. Still, I can't help wondering whether a Catelyn who can merely glower and point isn't an improvement after all...
I do hope there will be more insights to come on the Wall itself, now that we know it is quite magical and will neither let supernatural creatures from beyond pass nor Starks keep contact metally to their direwolves should they be on the other side.

To sum it up, some characters got interesting developments, but all in all I felt this was the weakest of the three books I read so far in this hypothetical heptalogy.