The new content serialization tooling combines the best of both TDS & Unicorn, making it much easier for you to script your content changes and move them between your different environments as part of your deployment process. Sitecore CLI provides a command line interface to interact with your Sitecore instance. This command line provides technical team members with automation capabilities and the ability to work at the command line directly with their Sitecore instance.
Sitecore for Visual Studio provides a graphical tool to interact with your Sitecore instance from within Visual Studio. This provides the same capabilities as CLI but makes it more accessible to users who are unfamiliar with command line tools. By using a remote rendering host, developers can build straight from Visual Studio into the rendering host and test changes without needing to recycle Sitecore every time. Make quick changes to the presentation layer, push those changes, and debug in a fraction of the time.