The early days of PPM include a growing store of advice, counsel on how to win in a PPM world. My thought is one of the most important and effective strategies is not yet getting the attention deserved.
Dave makes a great point. The level of granularity in the data we can see with the PPM is uniquely insightful.
Aside from what Dave mentions here, I would further recommend that each department in the station/cluster, especially Programming, Marketing and Promotions, track the activities and events happening inside and out of side of the station/cluster.
Ultimately, combining your diary/journal information with Arbitron ratings data, Media Monitors data and other market information will provide a comprehensive, multi-level tracking system to help you better determine how your station/cluster is performing under the PPM. Those insights will prove invaluable when crafting actionable strategies and tactics for operating in a PPM world.