1. A system comprising: a queue builder for generating priority queues; a computer mediated communications network for sending content data and subscriber data to the queue builder; an on-line queue manager for receiving the priority queues from the queue builder and for sending content segment play lists to the computer mediated communications network; and an exposure accounting module for receiving exposure data from the on-line queue manager and computing and outputting exposure billing data, wherein the queue builder is provided with profile editors through which rule developers create definitions by building data base selection criteria for extracting records with a common profile, wherein the queue builder accesses a disk storage that stores targeting data and rules for generating the priority queues, and wherein the disk storage is also accessed by the exposure accounting module to adjust priorities in order to meet exposure goals.