According to a report by the Wall Street Journal, Rosner is "closely involved in developing the new digital-textbook service."
The report also noted that the upcoming event, scheduled for Thursday, "isn't expected to focus on textbooks that exist today, but rather around tools for building digital textbooks."
A report by Fortune earlier today downplayed the subject of the event as being a "GarageBand for ebooks," quoting a publisher who said "Apple does not want to get into the content publishing business."
Enhancing Apple's existing iBooks, iBookstore
Apple's iBookstore, operated in parallel to the iTunes Store and App Store, already offers a way for publishers to market digital textbooks that can be used on iOS devices including iPad.
Last month, Apple introduced minor improvements to its free iBooks app with the release of version 1.5. The updated software added a night reading theme, full-screen mode and new fonts.
Apple also already offers basic support in Pages 09 for creating ebooks in the EPUB format used by iBooks. However, the reported involvement of Rosner in Apple's digital textbook initiative suggests an association between the iWork tools he currently oversees, including Pages, and the development and deployment of digital texts.
The iWork group originally developed iWeb, a tool for creating simple web pages that could easily be published through the company's MobileMe web hosting service. Rather than being bundled with Pages, Numbers and Keynote in the company's iWork productivity suite, iWeb was included in its iLife suite of media apps including GarageBand and iDVD, which it shared more in common with in its user interface.
A new direction for web development
Last year, Apple started selling its iWork and iLife apps as individual titles in the new Mac App Store, rather than bundled as two suites of apps in retail boxes. The company also abandoned both iWeb and its web hosting services when it shifted to iCloud.
In addition to changing the direction of its mobile cloud services, Apple had also shifted its strategy in web development tools over the past year and a half.
At the introduction of Xcode 4 in the summer of 2010, AppleInsider projected that the company's increasingly sophisticated, graphical software development tool could portend new HTML5 development tools.
Our report specifically noted that "one example of how the company's significant investments in creating Xcode 4 could be applied is in shipping a web development tool aimed at creating HTML5 content for the web and for use within web-based tools such as Apple's iAd mobile advertising program."
Six months later, Apple released a sophisticated tool for creating HTML5 content called iAd Producer. That tool is still limited to creating content intended for use with the company's iAd mobile advertising service.
It appears likely Apple's event will involve both enhancements to its iWork publishing tools and its iBook and iBookstore deployment tools for publishers, offering additional features optimized for textbooks.
Apple's event on Thursday is also expected to involve Eddy Cue, the company's vice president of Internet Software and Services, which involves oversight of iTunes, its App Store and iBookstore, as well as iAd and iCloud.