Take a look at the main Scrivener page with its link to the screencast:

http://www.literatureandlatte.com/scrivener.html

Then download and give it a test drive.

Be sure to visit the active and helpful forums.

The above justify a five star rating!!!

Hope you find Scrivener as useful as I do.

Bob

Adventures in time: http://homepage.mac.com/bobembry/free/

Blog: http://homepage.mac.com/bobembry/iblog/