From this great The Verge story, 

"Our friend Walt Mossberg may have retired, but that doesn’t mean he’s out of things to say: he’s signed a deal with St. Martin’s Press to write a book about the incredible rise of tech over the past 40 years, and what’s to come in the next decade. Tim Bartlett will be the editor.

The book is scheduled to come out in the early fall of 2019. “I’m going to take about a year to write it,” Walt tells me, suggesting his final column, https://www.theverge.com/2017/5/25/15686870/walt-mossberg-final-column-the-disappearing-computer, ; is “not a bad outline.”

https://www.theverge.com/2017/10/16/16480894/walt-mossberg-book-deal-personal-tech-revolution