Salvete!
That's what I thought - that the images weren't coming from the API ... but wanted to check. Owen might know best since he made most of these changes.
Confirmed. Cover images don't go through the API, so changes to the API don't affect them.
HOWEVER: I question whether Koha libraries are within Amazon's terms of service in using Amazon cover images. I think this is a legal grey area, where Koha's use may be technically a violation of those terms but a violation which Amazon has never responded to.
http://bibwild.wordpress.com/2008/03/19/think-you-can-use-amazon-api-for-lib...
Yeah, I've to say this has crept up at some of the deadly boring IP stuff I go to. It sure seems like it's still a very dirty pen. If you've not taken a look lately, cruise on by Open Library, cause their covers are definitely progressing along nicely. Also, George won't sue your arse.* (*Well, she might, but prolly not for the reasons Amazon would.**[** I assume you deserved it ifn she did.]) Cheers, Brooke