tedster - 6:29 am on Sep 30, 2012 (gmt 0)
The reason I asked about Image Search is that I'm hearing from other webmasters who lost search traffic on the same day - and it WASN'T from image Search. I'm beginning to think that there was also a regular Web Search update at nearly the same time - something besides the EMD.
I appreciate that not every traffic loss means an update - but I'm now suspecting that this past Friday/Saturday was both an image search update AND some kind of Web Search update as well. In fact, one of my long term clients lost an important page 1 ranking and about 40% of their total Google traffic - and they don't have an EMD, it's a branded domain.