I really hope this works out for Medium. Although $5/month is not a lot to pay for quality reading content (a book is like $10...) people have grown so used to paying next to nothing for content. Will be interesting to see if recent trends, like fake news and more awareness of clickbait, have people realizing that. Maybe our tastes for information will evolve like our appetite for fast food - we'll realize the crap we're stuffing in ourselves mentally. I'm optimistic.