NYTimes: When Does a Book Stop Being a Book and Become…?

E-books of the latest generation are so brand new that publishers can’t agree on what to call them.

In the spring Hachette Book Group called its version, by David Baldacci, an “enriched” book. Penguin Group released an “amplified” version of a novel by Ken Follett last week. And on Thursday Simon & Schuster will come out with one of its own, an “enhanced” e-book version of “Nixonland” by Rick Perlstein.

All of them go beyond the simple black-and-white e-book that digitally mirrors its ink-and-paper predecessor. The new multimedia books use video that is integrated with text, and they are best read — and watched — on an iPad, the tablet device that has created vast possibilities for book publishers.

The start-up company Vook pioneered the concept as a mobile application and for the Web in 2009, but with the iPad, traditional publishers are taking the multimedia book much more seriously.