YouTube’s HTML5 player has improved a lot lately and it’s almost ready to replace the Flash player. You can enable annotations and captions, the contextual menu lets you copy the embedding code and the video’s URL, YouTube now offers 480p and 1080p options for WebM videos and there’s native full-screen support if you use a Firefox nightly build or Chrome’s dev channel.
I’ve also noticed that sometimes embedded videos use the HTML5 player even if you’ve already installed Flash and you haven’t enabled the HTML5 trial.
