In his case, Scalzi watched sales of his book shoot up by 20 percent. But what’s even more interesting is that the sequel to Old Man’s War saw an increase of over 30 percent. Both he and Buckell benefited more from sales of books later in their series.

Not all Tor authors I spoke to saw such impressive numbers, however. Like the others, Daniel Abraham was approached by an editor to see if he’d be willing to give away his fantasy novel A Shadow In Summer. The novel is the first in a four-book series — the second was released last year — and its ebook format hit the web in April.

In a phone conversation yesterday Abraham said that he didn’t see any significant increases in Bookscan sales for either A Shadow In Summer or its sequel. Instead, the numbers stayed relatively the same. But he stressed the fact that he didn’t see a drop off in buys either and argued that regardless of sales figures the release still benefited his career.

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