I've read in the release notes that "some" videos may not play in the "emulator and simulator". I imagine this is the same on a real target device as well? So does the iframe embed from YouTube not recognize the user agent and serve Flash? Is that the problem? Or is there a way to get YouTube iframe embeds to work?
Just wanted to add that I get the player UI, but it always says, "This video is current unavailable.", when I try to play.