> The culprit -- whose copyright agent doesn't respond to DMCA takedown notices unless they come on law firm letterhead -- is none other than Amazon.com.
That's illegal. There are well-defined bullet points that make a valid DMCA complaint that must be acted upon, and I doubt Amazon would open themselves up to liability based on "big sticks". They'd lose safe harbor for not complying, which is extremely bad news for EC2 and any Internet hosting provider.