Hi @truescope,
Here is how I described it in our announcement thread:
This SDK is built on top of auth0-spa-js. The intention here is to abstract away some of the complexity of integrating auth0-spa-js with a React app. This SDK provides a solution for integrating with Auth0 that feels native to React. Specifically, it provides an Auth0 hook, functional and class component support, Typescript support, resulting in a generally easier and more efficient experience for React developers and projects.
Hope that helps,
Dan