Do you people

Seriously think that emacs and vim are superior to GUIs/IDEs?  Quit kidding yourselves.

I don't think vi is better than an IDE, however I do use it a lot.
Not because I think it's better but because it's on pretty much every *nix system in existence; this allows me to be able to sit down at any *nix computer and start coding without having to install anything.
I usually use an IDE on my personal computer though.