by andrewjw
There has been significant deployment of Key validators (for proof-of-payment) to many outlying stations including most of the Trenton Line. A "ring of steel" (to borrow from the MBTA thread) is going up at Market East and one will likely go up at each other other center city stations. Some stations including Market East platforms and Overbrook, have what look to be fare reload machines which can add value to a Key card but not issue a new card.