CBS reports that the Feds still view shoes as a real threat:

The joint FBI-Homeland Security bulletin, obtained by CBS News today, bluntly warns that terrorists are still working to use “modified footwear as a concealment method for explosive devices,” CBS News correspondent Bob Orr reports.

The alert follows the discovery of bomb detonators - expertly hidden in the hollowed-out soles of this pair of shoes - found aboard a European bus last month.

Intelligence officials say the shoes were not being worn at the time, but instead were being used, as the document says, “to smuggle electric blasting caps across international borders for use in a terrorist attack.”