React Email 2.0 has been released with several major updates, including a revamped preview server that allows for faster feedback and development experience. The new version features improved error handling, better user feedback, and faster boot up times. It also includes new components such as Code Block and Inline Code to make it easier to display code in emails. Additionally, the deployment process has been streamlined, allowing users to deploy their React Email apps directly to Vercel with ease. The update is compatible with various package managers and workspaces, providing a more predictable and hassle-free experience for developers.