Anyone who thinks this is actually going to happen needs to carefully read
http://www.nytimes.com/2006/09/03/us/03research.html

Summary: TSA is completely incompetent at procuring and deploying new technology. (I'm not sure the TSA is unique among government agencies in that regard; does anyone remember the billions that the FAA spent on the new air traffic control software some years ago that they had to cancel because they realized it was never going to work?)

My preidction: we're not going to see widespread deployment of high-throughput liquid explosives scanners until 2008 at the earliest.