You are joking, but it is true. I'm old and grew up on books - bookstores were my paradise, but I still feel the book format is kind of outdated. I much prefer smaller sized and self-contained pieces of information. When it comes to e-books, I think the ones that are less like traditional books and more embrace the possibilities of the medium are best. Klabnik/Nichols "The Rust Programming Language" is a great example, even more so Google's "Comprehensive Rust".
They're not joking, the thread that is linked is literally from 2010.
Well, based on how these sites work, this question is now resolved and needs no further discussion ever.