said by swintec:I didn't think it was an issue as well but the anonymous poster suggested it was. However the question then would be who is at the head of this chain and are there any providers who ignore or cannot be touched by this chain in any substantial fashion? said by AndrewW:
So I need to amend my initial question by requesting a list of Usenet providers who ignore DMCA takedown notices and cancel commands.
Cancel commands are really a non-issue to be honest. DMCA can affect any provider at any given time and none want to get the reputation that they "ignore" them. They may not get many or any, but as public discussions continue about them ignoring them...this information moves up the chain and does not go unnoticed.