Ranked in these QuestionsQuestion Ranking
Pro Emacs specific
Pro Uninterrupted workflow for common tasks
Simple tasks, such as commits, can quickly be made without leaving the editor.
Pro Easy use of git options and configuration of common tasks
You can easily change options of common tasks and either remember them as default for future use, or use it only for this command. Things like ignoring whitespace in diffs are good example of that.
Pro Easy to fix diffs
Since it's integrated with Emacs, diffs are very easy to fix. You can jump right to any file you want to fix as soon as it comes up in the logs or in the status view.
Pro Easy to remember mnemonics
You can easily learn the mnemonics for the most common tasks and use them to your advantage to speed up your workflow.
Con Useful only for people who use Emacs
Magit is only useful if your text editor of choice is Emacs. It wouldn't really make any sense to open up emacs just to run Magit if you use another editor.