The example used is the literary marginalia of famous authors, such as Twain or Kerouac--marginalia the average reader is unlikely to ever see. But it serves to illustrate a point about loss and gain.
Weinberger concedes it would indeed be a loss not to hold the book Kerouac held, read, and interacted with by transcribing his thoughts upon the text and margins of the page that inspired those thoughts. He uses the word "thrill" to describe the experience of handling a book containing such marginalia.
Ian Frazier used the word "sublime" in his New Yorker article on the same subject, albeit in a setting more conducive to using that word. It was Frazier's article that led to Weinberger's blog post. The distinction between "thrill" and "sublime" might parallel the distinction between attitudes toward traditional formats for literary matter. "Sublime" would certainly seem to connote an incomparably greater connection or attachment to the annotated codex than would "thrill."
Weinberger sees a trade-off looming, one that should actually be more beneficial to readers in the digital book arena. The potential to create digital marginalia, especially in a social reading environment, will negate (and then some) the loss of of an author's handwritten notes in the margins of the printed page. Specifically, Weinberger asserts:
We will gain the ability to learn from the digital traces left by all of today’s Kerouacs, Kerouac scholars, and Kerouac readers.To that, I would add: As long as those digital traces can be read or accessed via whatever medium is currently in vogue. Will historically significant digital marginalia from the year 2016 survive more than 200 years as has the marginalia in John Adams' books, which are currently being shown around the country in a traveling exhibit? I pondered the ephemeral nature of all things digital in this Bibliophemera blog post last year.
An interesting thread of comments follow Weinberger's thought-provoking post (Joho link above).