Steve Yegge wrote a comment on his blog:
All of the greatest engineers in the world use Emacs. The world-changer types. Not the great gal in the cube next to you. Not Fred, the amazing guy down the hall. I'm talking about the greatest software developers of our profession, the ones who changed the face of the industry. The James Goslings, the Donald Knuths, the Paul Grahams, the Jamie Zawinskis, the Eric Bensons. Real engineers use Emacs. You have to be way smart to use it well, and it makes you incredibly powerful if you can master it. Go look over Paul Nordstrom's shoulder while he works sometime, if you don't believe me. It's a real eye-opener for someone who's used Visual Blub .NET-like IDEs their whole career.
Emacs is the 100-year editor.
The last time I used a text editor for writing code was back when I was still writing HTML in Notepad about 1000 years ago. Since then, I've been more or less IDE dependent, having used Visual Studio, NetBeans, IntelliJ, Borland/Codegear Studio, and Eclipse for my entire career.
For what it's worth, I have tried Emacs, and my experience was a frustrating one because of its complete lack of out-of-the-box discoverable features. (Apparently there's an Emacs command for discovering other Emacs commands, which I couldn't find by the way -- it's like living your own cruel Zen-like joke.) I tried to make myself like the program for a good month, but eventually decided that I'd rather have drag-and-drop GUI designers, IntelliSense, and interactive debugging instead.
It's hard to separate fact from fanboyism, so I'm not willing to take Yegge's comments at face value just yet.
Is there a measurable difference in skill, productivity, or programming enjoyment between people who depend on IDEs and those who don't, or is it all just fanboyism?
First let me say, I am a self professed true believer in the cult of Emacs.
That said, the blogger is nuts. You write in what you find useful. I find that Emacs helps me, mainly because I spent my college years pre-paying the start-up cost of learning how to modify it to suit my needs, and modifying myself to its needs.
But other people do things differently, and as they say "That's OK".