"Wall box" is a kind of postbox, please reference wikipedia - Wall box. because this software is a box used to receive Facebook notification, and embed in the system tray, so i'm naming it "wallbox".
about direct using facebook icon, based on facebook policy, we don't want to use facebook icon at all. thanks many people in OMG! Ubuntu!, you give us many opinion for wallbox icon. we will discuss and improve original design.
please leave more comments (on here or OMG! Ubuntu!) for us reference.