This entire post came about due to a great screencast by Addison Berry about using secondary menus. If you haven't already seen the screencast or you don't understand how to make the children of the primary navigation show up as the secondary navigation then you must watch the screencast.

I'll come out and say it, before watching this screencast, I didn't even know using the children of the primary navigation as a secondary menu was even possible.  I had always used the secondary navigation for things like footer navigation and created individual menus for the various sections of the site and placed each block.