What is Upfront and Upfronting?

In Web 2.0 vs. Traditional: The inability to think outside of one’s self, Jonathan Trenn talks about “upfront” and “upfronting” and I didn’t know what that meant, so I asked and Jonathan enlightened me, “Upfront is a time period when the TV networks display their schedules for the upcoming season to major marketing decision makers. This gives top marketers the chance to bid on slots that they think would serve them well. Often the rates can seem to be favorable.” Very interesting.