Amazon has de-listed the book. Shortly after the post appeared on HN, someone from Amazon contacted me and told me it was being taken care of. A couple hours ago I got an email from the copyright group responding to my original notice saying the item was being removed and it might take 2-3 days. But it seems to have taken a lot less time as it's now gone

I've asked Amazon if it's possible to make the process more visible and suggested any content with common licenses (searching for a link to creativecommons.org for example) would be wonderful.

I'm obviously very thankful, but I do wonder what the outcome would have been without the visibility HN brought to my litte issue.