Is anyone using HTML 5 on their sites yet? I heard Youtube and Vimeo is using HTML 5 on some of their videos.

Also, where can I find out what the differences between HTML 5 and HTML 4, as well as which browsers currently support HTML 5?

I'm not using it yet. I believe it will take a while before people start using HTML5 because of browser compatibility issues.

I believe most browsers (latest versions) do support HTML5 apart from IE.

Check this article for differences between the two.

HTML5 is the proposed next standard for HTML 4.01, XHTML 1.0 and DOM Level 2 HTML. It aims to reduce the need for proprietary plug-in-based rich internet application (RIA) technologies such as Adobe Flash, Microsoft Silverlight, Apache Pivot, and Sun JavaFX.

The one thing that concerns me about HTML5 is that the media are promoting it as a 'Flash killer'. I think that this is misunderstanding. The truth is that Apple don't want to be competing with Adobe for content delivery and have done everything in their power to try to kill Flash on their devices (ie. iPhone, iPad, etc.) and have sold a story to journalists that Flash isn't required because HTML5 will make it redundant. I doubt that, and considering how the web experience for major sites would be without Flash, I would be cautious to put all of our hopes & dreams into HTML5 being more than a natural evolution of HTML.

Myles

Thanks Steve for the link! Myles, would Apple really have that huge of an influence on the standards guys? I couldn't imagine the web without flash myself so I wonder how things will go over once HTML 5 gains more popularity.

The HTML vs Flash has become somewhat of a diplomatical morning argument here with our developers and myself, however the consensus based on common sense would dictate that if the SWF format where to die why would adobe have continued and are continuing to pour money into the development on the once macromedia flash.

After Adobe purchased macromedia I doubt they had short term gains in mind, despite that the fact that flash isn't solely for animations. It also is for vector image creation and supports a number of other formats compatible with the cs4 range and other practical applications (gif, mov etc). As a result flash as a package won't disappear and nor do most think that html5 would have the ability to kill it off, anyone who has made a flash based or larger more complex flash elements would at the time be pulling their hair out with the use of an IDE, with code I think they may have attempted to bludgeon their computer with the mouse.

As you can probably tell it's a heated discussion here at the moment but thats the gist, none the less the new features look interesting but not ominous.

Hello,
HTML has been the basis for nearly all internet coding since websites first began to appear. There have been a few changes, such as ASP and PHP, which allow server side processes. But in essence, the long standing HTML 4 has not changed for quite some time.

The most recent version of HTML 5 is still very much under development, which has been slowed by the competitive browser market (Firefox, Chrome, and IE). Nevertheless, HML 5 is looking very promising, and promises to remove the need for many of the multimedia add-ons which we currently use with today's browsers.
Thanks