SQL Developer's Product Management team seems to be off-line today after a busy week at Oracle OpenWorld.
I would give this a bump next next week.
The SQL Dev product manager, Jeff Smith, is constantly giving demos at many conferences. Next time you get to an Oracle conference, check to see if he is giving a presentation. They are well worth attending.
Have you looked here: SQL Developer Learn More
There is lots of info there on how to use SQL Dev.