One of the long touted facets of the shift to digital reading is that it enables publishers and platform providers to glean data about their customers' reading habits. But with the data now flowing in, are publishers ready to put it to use?

“The owners of e-book platforms now have unprecedented and previously unattainable knowledge about how people read,” noted CCC’s Chris Kenneally, who moderated a closing Digital Book World panel on reading data. “They see every time an e-book is opened; on what device it is opened; how fast it is read; whether passages or entire works are re-read, and perhaps most dismaying for authors which books are never cracked, or never finished."

So what have we learned so far?

For one, more than half of all digital readers read on more than one device, noted Jared Friedman, cofounder and CTO of subscription service Scribd, and 10% of Scribd users read on three devices or more in any given month. “As people become more familiar with e-books and e-book reading services, [reading] is permeating their digital lifestyle,” Friedman said.

David Burleigh, director of marketing and communication, OverDrive, Inc., which facilitates library e-book lending, agreed. “We’re seeing about 40% of users reading on more than one device,” he noted.

Michael Tamblyn, president and Chief Content Officer, Kobo, which is a global provider, said the data was different in different locales—for example in Japan, where e-readers are not popular, and in Europe where more readers finish books on their digital devices, while U.S. readers are the "most fickle." He said most readers' habits remain fairly stable, but noted that romance reading did spike in summer, and health books did spike around New Year's, although Friedman pointed out that his data showed that only about 5% of Scribd users who opened a “new year’s resolution” book on health and fitness completed it—while readers of romance, by comparison, had about a 30% completion rate.

But the data is far from complete, and the panel agreed that fiction and nonfiction reading is fundamentally different. A nonfiction reader might get what he or she needs from a small chunk of a book and be totally satisfied, Tamblyn noted, where if a fiction user stops reading a book, its because they are dissatisfied.

For library user, Burleigh said it was even harder to draw conclusions about reader satisfaction because book lends are time-limited, meaning readers often don't finish in two or three weeks. Burleigh said that for OverDrive’s top titles in 2014, Gone Girl, Unbroken, and The Fault in our Stars, 30% only made it halfway through, while just 6% to 11% finished.

Micah Bowers, founder and CEO, Bluefire Productions, which provides e-reading services across a range of retailers and devices, echoed the rest of the panel, and said Bluefire also saw around a 30% average completion rate. But whether or not books are completed on a device, Bowers noted, there is clearly significant reader engagement.

“One of the interesting things to me is the amount of time people spend reading,” Bowers said. “According to our stats, about 35% read for over an hour every day, and 17% read for over two hours every day. That’s pretty significant chunk of people reading for significant time.”

That ability to assess “engagement” cuts to the heart of what data enables, observed Tamblyn.”'People who bought this also bought that is interesting',” he said “but getting a sense of whether you are engaged with a book, whether you stayed up through the night to finish it, these are the things that help us from a recommendation perspective figure out do we put that next book in front of you from the same author, or how quickly should we feed you next book in a series, or should we walk you toward another author.”

But the biggest question, Kenneally asked, is how prepared are publishers to understand and to seize the opportunity data provides?

There’s a long way to go before the data now collected is “actionable” Bowers said, but there is definitely interest. “It really comes down to a several hundred year-old industry that is only beginning to have access to this kind of data. It is incredibly new and it is going to take changes within the organizations.” But data can have an impact on decisions across a publisher’s business, he insisted, whether its search engine optimization, or content structure, marketing or who you give that next big advance to.

“All the things publishers do can be highly informed by data,” Bowers said. “But in a lot of ways, it is not a matter of having the processes and job roles and the best practices and so forth, so much as it is counter to tradition, and ego. There was a time where there was a magic to these decisions, that data might take away. And that can create fear.”

Tamblyn agreed. “There is apprehension institutionally because decisions can now be evaluated in a different way,” he said. “And that is anxiety-causing for some people who are worried that their decisions might not be looked on favorably.”

But the way he looks at data, Tamblyn said, is positive. “Before you had basically two ways to evaluate success. There is the critical response, and unit sales. [Data] brings the reader into the picture.”