If memory serves me right, this is my second favorite of the 8 (7 for those that don't count the Wind Through The Keyhole) in the Dark Tower saga. As of right now though, it's my favorite.
The last two books were all separated in their own parts, but this is the only one that really felt like each part was an episode. Not that I gave any mind to it, I like it actually. Each part was it's own self contained plot point that was resolved with a few threads to carry on to the next part.

The Wastelands is where things no longer become just Roland's journey. It's a group effort, only these episodic parts focus more on Jake and Eddie than Susannah's and Roland's POV. Susannah's points tend to come in for the future, but for the most part she's just following through behind Eddie. Roland is quieter in his train of though, giving way for Jake to not only come back (WOOO and also a damn you, because, well you all know, maybe?) but to grow further than just the boy that Roland dropped.
That's all i'm willing to say, or I may just go into spoiler rants.