TSA is apparently considering a yearly subscription service, mobile enrollment, and 'taste' of PreCheck for those who enroll on the spot.

They seem to be disappointed in the yearly enrollment numbers. Though personally, I don't think PreCheck has ever been about reducing risk or shortening lines. I think PreCheck is more about DHS gathering more and more intel on who is traveling through the country. People tend to forget that the name of the program is not Pre, it's PreCheck - because applicants supply copious amounts of personal data and agree to having their backgrounds investigated with this information, hence, the program is really a Pre-flight Background Check. And the more people who hand over this information about themselves, the larger the government's database becomes.

USAToday - Interested in TSA PreCheck? It might soon be cheaper and easier to sign up