Ask HN: Why emacs over vim?

Seeing this list of quite famous people [1] using emacs I wonder ... why do they all use emacs instead of Vim? I admit that I have never _really_ gave emacs a good go because all the meta keybindings seemed really foreign to me coming from a long term Vim user. If I am comfortable with Vim, is there any reason for me to switch? What are the main gains from using emacs over vim?

Just to throw some oil on the fire: 4 spaces for indentation

[1] http://wenshanren.org/?p=418