The title is a little misleading. What they've done is effectively created hundreds of snapshots of neural connectivity, each focusing on how one particular region of the brain hooks into another. The goal is to make this data available so experts and hobbyists alike can potentially identify connections that offer insight into brain function and disease.

An analogy would be trying to reconstruct the street layout of a city by taking pictures from a plane as it flew over. Each time you fly past, you might get a different angle, different weather conditions, or try a different camera. Now you have hundreds of photos, and you are hoping people who know things about cities will find useful information there, like where the best restaurants might be located.

Disclosure: I worked on the front-facing side of this project (data browser and image viewer).