It looks like their current plan for monetization is a per user subscription fee for added features on the notebook: https://observablehq.com/teams
Given the marketing on the page, it also looks like it's targeted at business use cases (i.e. a bunch of data scientists who want to visualize something in d3 but also want to collaborate).
Given the marketing on the page, it also looks like it's targeted at business use cases (i.e. a bunch of data scientists who want to visualize something in d3 but also want to collaborate).