Interesting stuff this:
Analysing reading data is playing a crucial role in the evolutionary growth in Amazon and Barnes and Noble. For years, those two companies have been guarding their data and not relaying it to their publishing friends. This data is exploited to promote books that are fashionable in any given day and the ones people tend to read, cover to cover.
Scribd has only been offering their eBook subscription platform in October and already they are massing a treasure trove of data. The longer a mystery novel is, the more likely readers are to jump to the end to see who done it. People are more likely to finish biographies than business titles, but a chapter of a yoga book is all they need. They speed through romances faster than religious titles, and erotica fastest of all. “We’re going to be pretty open about sharing this data so people can use it to publish better books,” said Trip Adler, Scribd’s chief executive.
Eoin Purcell's Blog 
From a publishing point of view I can see that data driven decisions will take some of the burden off the genius of the commissioning editor. Slightly uneasy as a writer though. That what we write about might be dictated to us even subconsciously by data…a new art perhaps, to write from the muse…and the data ‘muse’. My instinct is to go with all of these developments in the interest of pioneering for literature on all frontiers, but always in the background the astonishing ‘Fahrenheit 451’ by Ray Bradbury burns in my mind. What will this data really tell us about the majority? (they forward through slim plots in erotica to get to the juicy bits, they have no patience to work out for themselves who done it in a detective mystery, they read in handy small chapters, short sentences etc). I hope the custodians of all this data don’t ever turn evil!