As the latest firfox came up was were happy to read the below in there site :

"Currently, an entirely new spec is being drafted for file objects and handling within HTML5. It will provide a much more robust interface for accessing content in local files, in addition to extending functionality for file objects within Javascript/DOM. The primary additions include:

* Drag n' drop of local files into a web page.
* Asynchronous file data access via callback methods.
* Sending file objects via XMLHttpRequest.
* Improved file dialog window that allows for multiple file selection and file-type filtering (bug pending)
* Manipulating files with JS worker threads via postMessage (bug pending)
* Storing file objects within the localStorage/sessionStorage APIs (aaaaand bug pending)"

Was trying HTML5 with beta relases of firefox 3.6, the below the tags i liked the most.

My Top 10 HTML5 tags :

1.audo and video tags : say yes to OGG.

2.ruby tag : define a ruby annotation.

3.output tag : use output of scripts.

4.embed tag: can be used to embed plugins!

5.dialog tag: converstational output.

6.canvas tag: container for graphics.

7.datalist tag: a dropdown list !

8.articel tag: defines an article.

9.nav tag: for nativagtion keys.

10.mao tag: defines a map image.

So what are you waiting for experminet and enjoy GET FF