But as High-Def Digest reader Phillip Reece recently wrote in, apparently easter eggs have been with us since the launch of HD DVD, and the release of Joss Whedon's 'Serenity' back in April.
"From the Serenity HD-DVD's main menu, highlight 'Extras' and then press LEFT twice on the remote. This will bring up a hidden Serenity logo, which will take you to the 'Fruity Oaty Good Time' featurette."
The 90 second featurette was also included as an easter egg on the standard DVD release.
In fairness, this is not the first easter egg content to be discovered in a high-def disc release -- some studios have opted to "un-hide" content that was previously offered as standard DVD easter egg content, making such content directly accessible from the menu of high-def discs, while Sony has included monitor calibration test patterns as "easter eggs" on all of their Blu-ray releases thus far.
But the 'Serenity' featurette is the first true content easter egg to be reported to us here at High-Def Digest.
If you've spotted other easter eggs on HD DVD or Blu-ray discs, please let us know via our Feedback Form and we'll publish them to the site.