Was it quality traffic or junk? IIRC we get good conversions before the drop. I wish somone would hack Google! It would be very interesting to see what happens if they went down for a day or two. What I also don't get is when this happens the SERP's look normal for us, the tools we use to check rank show no problems? It's almost like it is the traffic throttling side of the algo that has the issue? Maybe that explains the foreign junk? Google sends users to the wrong sites? I really don't know.