Airings store the basic information about when a specific Show will air next or has aired. It can be populated by an RSS Feed from popular Telvue or Cablecast playback servers or used to push scheduling information to a playback server.
This module is the successor to the Open Media Airing module. Instead of defining an Airing as a node, cm_airing defines an Entity. You can add fields to an Entity the same way you would any other content type, but entities are kept separate from your node content. Since many stations have tens (if not hundreds) of thousands of Airings, this helps with performance, permissions, and general sanity for site admins.
To use Airings with Feeds, you'll need the dev snapshot of Feeds.