Facebook has opened an HTML5 developer centre and is urging developers to use it for apps development.
Have a look at HTML5 Resource Centre.
The site provides sections on building web apps and games, testing and distribution, along with a showcase of what Facebook considers standout examples of HTML5-powered apps, demos and games.
Developing Deploying Testing the app entire thing is covered in this resource.
Facebook has done a wonderful job of gathering HTML5 resources and putting it together in one place.
There are live application and demos which you can go through.
Thanks Facebook for putting up such a wonderful resource center to help HTML5 grow :-).
Lets HACK and try the new HTML5 Facebook SDK.And if we are stuck some where here is a wonderful HTML5 group :-)