The document discusses Observables and how they can be used with React. Observables turn event streams into collections that can be manipulated similarly to arrays. They allow asynchronous code to be written in a declarative style using operators. While Observables have not been fully integrated into React yet, the document provides examples of how they could be used to manage real-time data and animations. It also discusses modeling component state as an Observable stream, combining Observables with Flux architectures, and areas that were not covered like backpressure and schedulers.