There are two pins on the GPIO on the new B+ all to do with EEPROM. Now, it doesn’t really matter to most users what these pins do, but for those who are developing add-on boards that plug into the pins, it could make all the difference. According to James Adams of the Raspberry Pi Foundation, these pins can be used to allow add-on boards, called HATs (Hardware Attached to the Top) to program the Pi on boot-up and create new and exciting behaviours. You can read the current technical specs and documentation by visiting this GitHub site (although it’s currently a work-in-progress) and you can hear more from James about the potential of the EEPROM pins by reading this interview on Raspi.today.