I've read through this thread, and it looks like the "good" folks at spamcop have developed a hatred of Yahoo--it's become personal. Unfortunately, that doesn't do users who are getting delisted from Yahoo accounts because of refusals to deliver mail from their servers due to spamcop listings any good.
What's so funny about this is it sounds like, from the thread, that spamcop has other options than simply delisting Yahoo permanently--apparently Yahoo uses "nonstandard" headers, and bounces to forged addresses. Perhaps spamcop should, on that basis, change their software to look for those nonstandard headers (although it looks like that has now changed, and Yahoo is using standard headers), and not worry about bounces to forged addresses from Yahoo servers.
Instead of worrying about where to place the blame, and screaming and yelling at people about Yahoo's problems (which the posters here cannot control), FIX THE PROBLEM. I don't care if it's Yahoo's problem. If you have the ability to fix it, then fix it. It's like going to a mechanic to have your brakes fixed, and he says, in a tone of indignation: "I'm NOT going to, it's the manufacture's fault that they're broken!"
I've sent a request to my hosting provider that they stop using spamcop as a service, not so much because of the problems I'm having, but because of the ATTITUDE I see on this forum.
Fix problems, not blame. Maybe when spamcop starts losing business because they won't adjust to the world around them, instead just yelling in self righteous indignation, they will get the message, and figure out how to fix this on their end.