Garypen, you make a good point about CalNat having fewer ingredients for potential contamination.
I emailed Naturapet just a few days ago from the Innova dry cat food page, told them I was glad they tested for melamine and cyanuric acid, and asked if they also tested for acetaminophen.   I received this response a couple days later (copied and pasted directly from the email):

  We can assure you that there is no acetaminophen in our products.  All of our products are safe and non of them are involved in any of the recalls.  Please view itchmo.com for the newest information on the FDA findings on acetaminophen and how they tested the same food and found no traces of the substance. 
 
Thank you,
Customer Service

Evidently Natura trusts the FDA enough to give acetaminophen testing a pass.  While I'm glad Natura apparently reads Itchmo, it's obvious they missed the point that Itchmo isn't buying the FDA's take on  the acetaminophen poisoning, and that not everyone is as reassured.  I wrote back, but since I had inquired just to satisfy my own curiosity rather than because my kitties are having problems with their food, I didn't call, which probably would have been more productive.   But I would feel better if Midwest Labs could test for all the toxins and to the same levels as ExperTox.    That said, I am okay right now with feeding my kitties Innova.   They'll be going to the vet this week for routine check ups.
I would also be interested in hearing theories of how acetaminophen got into the pet food...

Hi Garypen
    So if the expiry date is 11/22/08, when was it actually canned?   Do we know when Natura started canning exclusively at the plant in S. Dakota?   (I'm not implying anything sinister; I'm just wondering.)   I