You can call me cynical if you want, BUT :
There was no apology -- they merely said they wouldn't sponsor PetFestAmerica next year -- I'm guessing that they will just be funneling the $$ they spent on PetFest to HSUS in some other (more clandestine) manner. Iams affiliation with HSUS still exists.
The HSUS Vet is still on the Iams advisory board -- Iams was asked to replace the HSUS Vet (Dr. Andrew Rowan) with a "Sportsman Vet -- Iams declined to do so.

I agree that all of us contacting Iams did some good -- Iams has taken a small token step in the right direction, but this is only winning one small battle -- the war is still on.