In case you were wondering:
"About the Visualizations
The visualizations in Data USA are powered by D3plus, an open-source visualization engine that was created by members of the Datawheel team."
I haven't explored it too much yet, but I'm enjoying the breadth and succinct presentation of all this information in one place.
The visualizations only initiate when they are visible in the window. When that happens, they make an API call for the data and then initialize the D3plus visualization.
All of the visualizations use shared attributes, for things like location names and industry colors/icons. Those API calls are stored in the browser using localforage. https://github.com/mozilla/localForage
Several of the visualizations use data from ACS summary tables and the axis in several of the visualizations reflect the underlying buckets provided by the Census Bureau.