Created by Mike Bostock
There are some good questions, comments and links over at Hacker News - ycombinator
It's been in development for over a year, and was released end of January 2018.
YOUTUBE uEmDwflQ3xE Observable: An Earthquake Globe in Ten Minutes
Wrote my first @observablehq notebook today after reading docs for 30 minutes. I explain how federated wiki renders pages with dynamically loaded plugins. If you like coding in the chrome inspector then you are going to love Observable. tweet