The conclusion of the Twilight Saga.
Immediately in the table of contents there is a surprise waiting: the book is split up in three parts. The first is rather short, and as in the other books told by Bella. Then, it flips to Jacob's point of view, followed by the finale where you again follow Bella on her adventures.
In the last book, Edward convinced Bella to marry him. What follows here is the period of time between Bella keeping her promise and Edward keeping his -- the final transformation to a Cold One, a vampire. They plan it so that Bella can be away from her family during her first days as a new-born, to spare her the agony of craving their blood, not wanting to hurt them. Before that, however, they head off for their honey moon, to to southern America and from there by boat. Bella, getting her wishes through at the island, finds herself in her personal heaven, and would rather not return to school at all when the honey moon approaches its end. Things do not quite work out the way they had planned, and are abruptly forced to head back home when Bella's health mysteriously starts degrading.
Instead of getting to know more about what's happening, we're presented with Jacob's point of view -- which was indeed frustrating, as it somewhat stalls the story, but Stephanie manages to pick up speed and make Jacob's angle add flavor to the story. His agony of not being able to help Bella, and how his view of the vampires changes gives more depth to the person behind the wolf.
Eventually, the story returns to Bella, and the conclusion of the story. Her special ability proves both interesting and useful in the ending scenes, where the world is turned completely upside-down for Bella and her new family -- very harsh, yet full of love.
Trying to put the book down during the final chapters of the book is an exercise in futility...