Although "thrilling conclusion" is a cliché, Stephenie Meyer wraps up the Twilight vampire series with panache. The names of the books in the series are not helpful in telling the sequence (compared to "Sunrise", "Noon", and "Sunset", for example), but this is the fourth and concluding book, and readers should start at the beginning and read the series in order, saving this one for last.
The story opens with Bella on her way to happily ever after: a wedding with Edward. Fairy tales may end with a wedding, but the number of pages is an indication that nothing between Bella and Edward is ever that simple. First comes their honeymoon - with Bella still human, and Edward a vampire. The intimacy that the couple (and the author) avoided through three lengthy books is now timely. Meyer describes it delicately but effectively.
What follows is cataclysmic. The werewolves, the Cullen family of vampires, every vampire group previously mentioned in the series plus a few more are thrown into conflict, and naturally Bella is in the middle of it.
As in Eclipse (book 3), Jacob Black is the character who surprises. The vampires don't seem prone to character development. Being a vampire is all about immutability. Jacob, the werewolf (all about changing), is the one who, with much inner conflict, is able to take a step forward and choose his path. To an extent, it is chosen for him, but he makes way more hard choices than, for example, Bella does. Bella falls in love with Edward, and then makes that her number one priority. Jacob picks his way among actively competing loyalties to a place of peace.
Breaking Dawn was my favorite of the series. Truthfully, Twilight, New Moon, and Eclipse could have been compressed into one book, and spliced with a trimmed down Breaking Dawn into one unforgettable book. I know that will be sacrilege to some readers. As a jaded adult reader, I've enjoyed the series, but felt like Meyer was marking time, especially in New Moon and Eclipse. Perhaps Meyer will bring us more from the Twilight universe.