My understanding of the percieved threat of the lockers is that an airport worker who does not get screened could put something in a locker later to be retrieved by someone who was screened. The idea of the fingerprinting is to make sure that the some person who put the stuff in the locker is the person who takes it out.
Personally I'm glad to see the lockers return as I always used them and they'd be really helpful now that we have to get to the airport so early. I'd prefer not to be fingerprinted and hope that the decision is made to return to the old style combination lockers, but I'd probably use the fingerprinting ones if available.