Now, hundreds of thousands of book sales behind him, Scalzi says there is no doubt that the blogosphere played a critical role in the marketing of his novel. "What you get in the blogosphere is accelerated word of mouth--and word of mouth, or word of blog in this case, is an extremely powerful mover of books," Scalzi said. "In effect, Glenn hand-sold my book to 200,000 of his readers."

Scalzi felt so indebted to the blogger that he thanked Reynolds in the acknowledgements page of his sequel, "Ghost Brigades," which was published in February.

After Reynolds received the advance copy of "Old Man's War" he posted more than 20 items about the book between Nov. 22, 2004 and March 26 of this year, when the book was nominated for the prestigious Hugo Award for science fiction writing. Other bloggers to praise the book included Eugene Volokh of The Volokh Conspiracy and Stephen Bainbridge of ProfessorBainBridge.com.

The book was released in January of 2005, and bloggers had begun writing about it before it had even hit the shelves. Reynolds posted about the book first on November 22, 2004; Bainbridge posted about it on January 12, 2005, and Volokh on February 24, 2005.

Scalzi said he believed the large number of online sales was a direct result of blogger-generated publicity. He said Tor told him that the percentage of copies sold online was five to six times higher than their other titles.

"Anecdotally, what leads us to believe that blog chatter, starting with Glenn and Cory Doctorow at Boing Boing and then moving through the blog ranks, was important was that a rather outsized amount of the sales of ['Old Man's War'] were online--five or six times the amount that a book usually sells online, as a proportion of total sales," he said. "Personally, I have no doubt that Glenn was a prime mover, especially early on, since so much mail I got was 'Hey, I heard about your book through Instapundit.'"

"Old Man's War" had its genesis in the blogosphere, as well. Rather than pitching his book to publishers, Scalzi published the novel on his own blog, Whatever, and it caught the eye of Tor chief Patrick Nielsen Hayden. "After I had finished writing it I really didn't look forward to submitting it everywhere and waiting months to get rejected. I have a reasonably popular site of my own, so instead of submitting it, I decided to serialize it on my own site," he said. "When I was done serializing it, I got a letter from Patrick Nielsen Hayden saying that he liked the book and was wondering if I would let Tor publish it."

Word-of-mouth expert Pete Blackshaw, chief operating officer of Nielsen BuzzMetrics, said that--much like Oprah Winfrey's Book Club--bloggers can build up audiences that drive sales of particular brands or titles. "The principle is simple: influencers matter," he said. "Over the course of many years, and thousands of posts, Glenn Reynolds has made an unprecedented number of deposits into the 'trust bank,' and trust is the most important currency of effective advertising."

After the success of "Old Man's War," Scalzi received a deal for a sequel, titled "Ghost Brigades." Scalzi said that Tor leveraged the interest from the blog chatter to boost brick-and-mortar sales, as well. "The initial success of ['Old Man's War'] as an online phenomenon, among other factors, has spurred Tor to take advantage of the momentum and promoted both the trade paperback of 'Old Man's War' and the hardcover of 'The Ghost Brigades' to booksellers," he said. "I think Tor has been very smart to capture the online momentum of the book and help transfer it to brick-and-mortar sales, because bookstores still are where the vast majority of books get sold."

Scalzi is currently working on the third installment in the series.

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