Apple has released iTunes 11.3, bringing iTunes Extras for HD movies to the Mac — iTunes Extras has also been added to Apple TV within software update 6.2 for the set-top box. As noted in the release, “iTunes Extras can include behind-the-scenes videos, short films, high-resolution image galleries, director’s commentary, scenes, and more.” iTunes Extras will also be brought to the iPhone, iPad, and iPod touch with iOS 8 in the fall.
Previously purchased HD content will automatically gain the iTunes Extras content with any additional purchases necessary.
Update: With the update, Apple is changing the way it treats HD video files, as one download now contains all extras, and some movies start by showing users a screen more akin to a DVD menu.
A consistent Extras UI works across iTunes, iOS, and Apple TV, sometimes including even more content than was previously available. The Bourne Legacy, for instance, adds 5 additional featurettes to the two originally included.