There's been a lot of discussion lately about whether or not the HTML5 video tag is going to replace Flash Player for video distribution on the Web.
Consensus: While the video tag is a big step forward for open standards, the Adobe Flash Platform will continue to play a critical role in video distribution.
Click here for a discussion of this topic in the YouTube context (a pretty significant one).
HTML5 (and CSS3) are works in progress. While some parts of these specs are finished or stable, other parts are still under development or have no current browser support.
Nonetheless, leading development tools, e.g., Adobe's Dreamweaver, have begun to support these technologies. To wit, specs that are stable or that have some level of browser implementation are now seen in the new Dreamweaver CS5 HTML5 Pack. Select the Product Details tab.
While the official specifications are still not yet complete, they are now supported to varying degrees by a number of different desktop browsers – and more importantly by all smartphones using Webkit-based browsers (e.g. iPhone, Android, Nokia WRT, Blackberry OS). Given the recent surge of interest around HTML5, Dreamweaver CS5’s compatibility with HTML5 and CSS3 was updated so you can begin exploring their potential today.