These "take a book, leave a book" nooks certainly exist in my town, most often around schools and neighborhood community areas (the playground, pool, etc.).
As far as digital goes, I have never been one for e-books, never ever.
Reading to me is often an escape from the pixelated world, and the baggage and distraction that it can bring. For this escape to be successful, the printed page is always a prerequisite.
Sure, e-reader technology is convenient and impressive, but is there not always a cost to convenience? So far it's been environmental health, mental health, privacy...
So I will keep my printed books, and thankfully I don't think they are going anywhere.
Currently going through my backlog of late 90s/early 2000s web/interface/graphic design coffee table books, which are always of particular inspiration when I venture back onto the computer. My library also includes some art retrospectives, pictorial reviews of architecture, philosophy, non-fiction, and more.