The thing I like about Dungeon World over other systems is that it puts the fiction first. Everything that happens must be justified by the fiction. The checks and dice rolls are specifically designed to move the story forward and nothing that happens therefore is a dead end. I particularly like this idea given the fact that I only ever play solo, so any mechanic that drives the fiction is akin to a miracle as far as I'm concerned.
This book is filled with all kinds of advise, a lot of it you'll have come across many times in many other core books but some of it will lead you to an entirely new way of thinking. For example, when you roll the dice here, you're rolling for the consequences to your actions rather than just to see if you succeed. This means that there is always a narrative consequence to every action. It's kind of like a continual accumulation of fiction that results from each and every situation, and this is a true godsend when it comes to attempting solo play.
Very informative. Makes a change to see something really and truly different from an rpg core book.