Email Concentration and Automatic Filtering

The majority of the world's mail servers subscribe to these block lists. And woe betide you if your own mail server ends up on one of these lists, cause you will be cut off from the rest of the world,. But my newsletter isn't span mailman uses a double opt in verification system. I can only imagine that this is going to get worse over time. The once diverse world of email hosting has been denuded with two commercial providers dominating corporate paid for services and a couple more giant free web mail providers. This concentration means that the communications of tens of millions of people are dependent on the invisible, inscrutable and inexplicable decisions of the administrators for a small coteri