Improve security perhaps, but this pattern of throwing all sorts of technology at perceived security problems has me worried. Eventually we'll need to show up three hours before a flight just to go through all the machines. Oh, sure, a shoe scanner here or there might not cause much inconvenience, but what about all the other machines that are being considered for airport security checkpoints? The recent pilot program at MCO comes to mind... Everyone focused on the X-ray scanner for humans, but in that same pilot they were testing about 5 other security machines, including a walk-through device that blows air around and analyzes it for explosives, plus a special screening machine for liquids. At some point we must ask ourselves if we really need all these bells and whistles. After all, humanity has gotten along just fine for many millennia without any shoe scanning machines.