Comment 10 for bug 430720

I not sure what you mean by , "guidance would be appreciated for removing the explicit selection and leaving it back with the non-explicit default."

Human theme and the humanity-icon-theme *are* the default themes. This default to humanity-icon-theme was changed in Karmic. and is the default in Lucid as well.

If you are asking how to revert back to the old icon theme?
I'm not sure what you were using , since the screenshot only showed the panel which suggests gnome icons, Were the folders grey?
you could try the gnome icon theme or any other icon theme in the appearance prefs , keep trying until you notice the theme/icon set you were using.