I am in the process learning HTML 5 ,Jquery and CSS 3- I would be documenting my finding going forword as and when i come up with new tags.
Audio tag - This tag helps to display any type of audio information. This has options of specifying two sources. Based on the browser what type it supports, it will pick that. The another tag is Source tag.
<audio controls="controls">
<source src="Song1.ogg" type="audio/ogg" />
<source src="Song1.mp3" type="audio/mp3" />
Your browser does not support the audio element. - This will display in case if the Audio is not supported.
</audio>
Nav - this is another tag where you place all your primary navigation links for the site Embed - This tag is used for embedding an external application or interactive content into an HTML document.
Figure - This element represent the flow content,optional with captions , Self contained and Single unit of content with main document.
<Figure></Figure>
Canvas - Content can be draw on this. Games and images and shapes. Veryuseful tag.
HTML 5 - APIs -
DOM 2 Specifications are part of HTML5 now.
Video and Audio
Inline Editing API
Offline Application API
History API
Web Protocol API
Useful links
http://slides.html5rocks.com/#canvas-2d
http://ishtml5readyyet.com/ - This will tell by when the HTML 5 will become standard.