The activity monitor for Mavericks running on my 2013 MacBook Pro Retina lists a column "Idle Wake Ups" that is new to me, and Google and Apple Support Forum searches were unrevealing as to what it is telling me. I would welcome any advice about this measure and how I can use it to assess the activity of various processes.
Mavericks performs some advanced timer coalescing to reduce power consumption. Apple claims up to a 72% reduction in CPU activity. I think (but am still searching for written proof) that
Idle Wake Ups is the number of times the CPU leaves the idle-state per quanta of time. I'm not sure what that quanta is (probably one second).
You can read more about Maverick's power savings at Ars Technica's excellent review of OSX 10.9 (page 12, "Energy Savings").
According to Intel an Idle Wake Up is the
Number of times a thread caused the system to wake up from idleness to begin executing the thread.
Source: Idle Wake-ups (Intel.com)