http://www.w3schools.com/ is a very popular tutorial site. They have already started tutorials for HTML5 http://www.w3schools.com/tags/html5.asp
I see errors at http://www.w3schools.com/tags/html5_video.asp and http://www.w3schools.com/tags/html5_audio.asp autoplay ==> true | false controls ==> true | false As far as I know autoplay="false" also means enable autoplay in firefox. I wish somebody contact them to correct those and other errors. Otherwise people start using autoplay="false" to disable autoplay. and some vendors will start supporting that. while others will go by w3 standards Which in turn will bring trouble to user who surf the site using a browser which is not the one used by the web developer.