Apple released an update to iTunes today to version 11.3.

iTunes received an update today that includes new iTunes Extras for HD movies. In addition to viewing your favorite titles in beautiful 1080P HD video, you may now also receive behind-the-scenes videos, short films, high-resolution image galleries, director’s commentary, cut scenes and more! This new experience can be enjoyed on the Apple TV with software update 6.2, which is also available today.

iTunes Extras will automatically be added to previously purchased HD movies as the features become available at no extra charge.