petehall - 1:06 pm on Apr 13, 2012 (gmt 0)

Maybe this is the reason for such huge fluctuations in the SERPs...rolling out the changes one bit at a time on different servers in a rotational movement.

I think you are right, and long tail traffic appears to be getting better now which is great news. I've always worked quite heavily with long tail so was disappointed to see the quality drop recently.