How do you create animated presentation in screencast Here is a snapshot of the screencast I was watching. 

http://dl.dropbox.com/u/7468116/screencast.png

How do you create such animated presentation in a screencast. I know how to capture stuff I am doing on my computer as screencast but how do you build a dynamic presentations. What are the tools available for a mac user.
I've used ScreenFlow to do this a number of times.  It's very simple to use and worth the $100.  You can buy it off the website or from the Mac App Store.

Also, until 13 May 2011, you can buy it as part of the MacLegion bundle, which means you'd get it (plus a number of applications) for $50.  However, that will be a non-MacAppStore license: http://maclegion.com/