updated 06:25 pm EST, Mon November 21, 2011
Adds native full screen support and captioning
YouTube has been improving its HTML5 player. The app has incorporated several new features, including support for 1080p video. The changes increasingly make it a viable replacement for Adobe's Flash player, which is so far still needed to get the entire feature set.
Full-screen 1080p playback for WebM videos also comes along with 480p. Enhancements to the player include a contextual menu that simplifies the copying of the embedding code and web link of a video. Also added have been annotation and captioning.
Another new feature is native full screen support for some versions of Firefox and Chrome. [via Google Operating System]