October was all about Allegiant. In addition to setting HarperCollins records for publication-day sales, the final installment in Veronica Roth's Divergent series was also the most talked about book on social media in the month of October. "It wasn't even close," said Jeff Costello, v-p of CoverCake, which measures how books are faring on social media. "We've never had a book that dominated the conversation as much as this book," he added. Allegiant scored a 10 out of 10 on CoverCake's scale of how many conversations took place about the title, receiving twice as many comments as the second most popular book, House of Hades by Rick Riordan.

Elizabeth Smart's account of her abduction and rescue, My Story, came in third. Costello said that most of the comments about the title resulted from the "massive media exposure" that Smart received at the beginning of the month.

Catching Fire by Suzanne Collins reappeared on the list last month. The book has hovered consistently in or around the top 10 books in CoverCake's ranking for the entire year, according to Costello. In October, the first trailers appeared for the film version of the second book in the Hunger Games trilogy, due out November 22, reigniting online conversation.

Covercake's Top 10 Books In Social Media, October 2013

Rank Title Author Scale* Male Female
1 Allegiant Veronica Roth 10 42% 58%
2 House of Hades Rick Riordan 5 49 51
3 My Story Elizabeth Smart 5 39 61
4 Catching Fire Suzanne Collins 4 41 59
5 Sycamore Row John Grisham 2 52 48
6 I am Malala Malala Yousafzai and Christina Lamb 2 45 55
7 Doctor Sleep Stephen King 2 43 57
8 Lean In Sheryl Sandberg 1 38 62
9 The Goldfinch Donna Tartt 1 48 52
10 Killing Jesus Bill O’Reilly and Martin Dugard 1 37 63

*How many conversations took place about the book in question for every 10 comments about book #1