leadegroot - 11:35 am on May 16, 2010 (gmt 0)

In any event what real help is this to anyone beyond idle curiosity?

As a one off figure - no, not really interesting beyond prurient curiosity.
But if you track it over time and notice a drop - you know there is a problem.
It lets you try things and see if that makes you a more or less valuable publisher.
Its one more thing to compare against other changes:
'ECPM dropped, but my revenue sharing percentage didn't - so its not me, its a change in publishers."
This knowledge will lead to a different choice of actions to attempt to fix it.

Yep, I for one would really like to have this information and consider it a fairly basic necessity to a business relationship.