Augmenting Human Intellect: A Conceptual Framework (1962)

It also marks the 50th year anniversary of Ivan Sutherland's Sketchpad, which inspired/reenforced Engelbart to realize his ideas in this paper, to eventually become what you saw in his "Mother of All Demos".

It's a bit sad, 50 years later, we are still operating in the the same paradigm initiated by Sutherland, and so little in Engelbart's paper has been truly realized.

"WHOM TO AUGMENT FIRST

"The experimental work of deriving, testing, and integrating innovations into a growing system of augmentation means must have a specific type of human task to try to develop more effectiveness for, to give unifying focus to the research. We recommend the particular task of computer programming for this purpose."

So basically, Emacs.

The interesting part is that I found this paper (actually a list of references: http://kruhft.dyndns.org/item?id=151) through reading the the editor-people newsgroup/mailing list circa 1981 (through nntp://nntp.olduse.net). Its quite a lively discussion about editors, lisp and human computer interfacing in the days of ed with the new up and comers vi and emacs expanding the horizons of state of the art editing software.