New Keying Node questions...

I am looking for info on using the new keying nodes in the compositor. Specifically the “keying screen” node and the new “keying” node. I have looked at these
http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.64/Keying

http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.64/Keying/Implementation

and find them to be less than usefull. I have tried experimenting but am not getting very far. Would love to see some feature by feature tutorials.

c

Would love to see some feature by feature tutorials.
Buy the Tears of Steel DVD which has a workflow example using this keying node