HTML5 video
May 1, 2010 
From what I have read about HTML5, I think that it will make some changes, but it seems like most of the code is just a little different. The HTML5 specification was adopted as the starting point of the work of the new HTML working group of the World Wide Web Consortium (W3C) in 2007. This working group published the First Public Working Draft of the specification on January 22, 2008. The specification is an ongoing work, and is expected to remain so for many years, although parts of HTML5 are going to be finished and implemented in browsers before the whole specification reaches final Recommendation status.
HTML5 introduces a number of new elements and attributes that reflect typical usage on modern Website. Some of them are semantic replacements for common uses of generic block (<div>) and inline (<span>) elements, for example <nav> (website navigation block) and <footer> (usually refer to bottom of web page or to last lines of html code). Other elements provide new functionality through a standardized interface, such as the <audio> and video elements.
The HTML5 syntax is no longer based on SGML despite the similarity of its markup. It has, however, been designed to be backward compatible with common parsing of older versions of HTML. It comes with a new introductory line that looks like an SGML <!DOCTYPE html>, which enables standards-compliant rendering in all browsers that use “DOCTYPE sniffing”.
