Print on Demand services for classic D&D products.
This isn't terribly new, WotC had been providing some PoD services for some of their new D&D 5 materials. What is new that we are seeing some classic products out now and should expect to see more each week.
I picked up a copy of The Shady Dragon Inn. It was cheap, and I never owned a copy before. It is also something I can use in pretty much any version of the game I play.
I suppose in truth I should have grabbed something like The Secret of Bone Hill or Castle Amber; something I still have a physical copy of and can compare. Actually I should get a new copy of the 3.5 Draconomicon. My son used to take that with him to pre-school to read (and read and read) and my copy is really worn out.
This is the start of a new era for Wizards. D&D can now be perpetually in-print. This will also really kill the after-market book sales now. Oh sure, collectors will still want good original copies, but there will be plenty that will want playable copies too. I might pick up I10: Ravenloft II: The House on Gryphon Hill just so I don't wear my copy out anymore.
Imagine if all of the TSR and WotC back catalog was available for print on demand like this? This could open up older versions of the game in ways never before possible. Play a game at a convention and then hand a QR code on a card or send a link so people can get their own copies.
I do have a fear that this might hurt our local game stores though.