Wirelessly posted (8820)
From help app on the device:
Cell broadcasting is designed to enable wireless service providers to use SMS text messaging to send information to all BlackBerry® devices in a specific geographical area simultaneously. You can receive cell broadcast messages that contain a specific type of information by subscribing to a cell broadcast channel that provides that type of information. Different cell broadcast channels send different cell broadcast messages. For example, one cell broadcast channel might send regular weather forecasts while another might send traffic reports.