EFF has a great piece about the whole stir regarding the new TSA whole body scanners or Advanced Imaging Technology (AIT) as it's formally called. In essence TSA has moved aggressively to deploy the scanners at an enormous cost without validating whether the scanners address the threat they are meant to find - namely easy to conceal, hard to detect powder-type explosives. As EFF reports in their post, it turns out that the scanners are fairly easily confused - even by folds of clothing. Additionally these scanners were developed to detect more traditional threats - weapons, liquids, and more traditional explosives like C4 and plastique. Powder was not one of the drivers in the development of these scanners. EPIC has filed a lawsuit against TSA demanding that the deployment of the AIT scanners be halted pending an independent review of their effectiveness.
It's interesting that the EFF article quotes a former chief security officer of the Israel Airport Authority who calls the scanners "expensive and useless . . . That's why we haven't put them in our airport." Yes, and TSA should pay attention to the Israelis experience...they have had a successful track record at Ben Gurion airport and of keeping terrorists off of planes - and they don't need to "touch your junk"!