Well lockers are not prohibited by TSA -- it is just that they have new rules for them. MSP has a ton of lockers airside. I use them quite frequently when I have to make a same day connection between two different ittns. Just go out to the car and switch bags/repack, and then off back through security. I put the computer bag in the locker, and don't have to deal with that nonsense on the way back through.

TSA only required the use of a biometric (at MSP a fingerprint scanner) when using the locker. No actual personal information about yourself is obtained. So they have a fingerprint, but nothing else. What I think is that most airports were not willing to invest in the technology to keep the lockers open to the traveling public.