The new CLI tool 'Git who' transforms the way developers interact with git blame by offering a more user-friendly and efficient method, especially for large teams and projects. This tool allows users to easily identify which commits to 'blame' rather than focusing on the author of the changes. User comments reveal a mix of excitement and skepticism about the tool, especially compared to popular integrations like GitLens in VSCode. There are discussions on customizing the tool for different use cases such as managing multiple emails for commits and extending its functionality. The performance of git blame can be enhanced through caching strategies, which some users are exploring in their own projects.