We have already seen Google making steps towards getting YouTube to not require a Flash plugin, which is currently only supported in Safari and Chrome. Now they have made yet another step towards HTML5 support by providing a new embedded video option that plays the video in HTML5 or Flash depending on what device you are using when viewing it
You can check out a preview and example of the new embed code style on the YouTube API Blog.
If you use the new embed code style, your viewers will be able to view your embedded video in one of our Flash or HTML5 players, depending on their viewing environment and preferences.
An additional benefit of the new embed style is that it will eventually allow embeds to work on mobile devices, which typically use a built-in player instead of Flash or HTML5.
Before we make this new embed code the standard for our general users, we wanted to give our developer community a preview. While there may be some limitations, please try it out and let us know how it went.