HBO apparently intends to make this into a Rome-style TV series, with each book getting one season dedicated to it.
And yes, the last book was meh, I thought Brienne was kinda interesting but not anymore after what felt like 200 chapters of her bumblefuck adventures. I take heart, at least, in knowing it was really only half the book that GRRM had intended- it was too long for the publishers, so he cut out about 1/3 to 1/2 of the book and is going to put it into Dance of Dragons. Rather than leave storylines ending too abruptly, he just cut out all the chapters for particular characters; namely the good ones like Jon and Daenerys.