I can't recall if I have ever publicly discussed membership schemes for magazine revenue. It's not a new idea and sometimes it's really just semantics. When I was young, and I bought a subscription to the National Geographic they called me a member of the Society. I can't recall if I received anything special beyond the best printed magazine of its day, other than pride of being a so-called member of the National Geographic Society, but that seemed pretty cool at the time. And then there was Consumer Reports - that, too, was always called a membership. I have always been a fan of membership enterprises. In 1999 I was the COO of a membership organization called YAPA, the Young Adult Professional Association. Our plan was to be like AARP but instead of retirees as members we cultivated college graduates, with discount programs, job guidance and of course a magazine. We raised multiple millions of dollars and died an untimely death in the dotcom doom of 2000. It's still a great idea.
But here we are in the 21st century, and membership models are a "thing" again, but unlike the traditional publishing model, which is based on a transactional relationship of you give me money and I'll send you a magazine for a year or two. The new membership plans usually contain special offers, discounts, and many times a chance to meet your favorite editors and writers at events. I guess you could call it a 360 approach. I'm sure someone else already has. As American Express has said for years "membership has its privileges." The membership approach drives an affinity with the brand.
The New York Times has Time Plus, and the Wall Street Journal oddly has WSJ Plus. Both successful membership programs.
If ever I was to start another magazine, I would explore the membership model. It wouldn't work unless the magazine and the content was something special. With unlimited content everywhere on the planet why go into a new publishing business, if what you have to offer isn't excellence itself?