I'm currently reading The Design of Everyday Things by Don Norman, which has a bunch of seminal ideas about how to make the technologies we use every day more friendly and obvious.
He has some interesting things to say about the effect of technologies on how we write:
FROM QUILL AND INK TO KEYBOARD AND MICROPHONE
In earlier times, when goose quill and ink were used on parchment, it was tedious and difficult to correct what had been written. Writers had to be careful. Sentences had to be thought through before being set to paper. One result was sentences that were long and embellished—the graceful rhetorical style we associate with our older literature. With the advent of easier to use writing tools, corrections became easier to make; so writing was done more rapidly, but also with less thought and care—more like everyday speech. Some critics decried the lack of literary niceties. Others argued that this was how people really communicated, and besides, it was easier to understand.
With changes in writing tools, the speed of writing increases. In handwriting, thought runs ahead, posing special demands on memory and encouraging slower, more thoughtful writing. With the typewriter keyboard, the skilled typist can almost keep up with thought. With the advent of dictation, the output and the thought seem reasonably well matched.
Even greater changes have come about with the popularity of dictation. Here the tool can have a dramatic effect, for there is no external record of what has been spoken; the author has to keep everything in memory. As a result, dictated letters often have a long, rambling style. They are more colloquial and less structured—the former because they are based on speech, the latter because the writer can't easily keep track of what has been said. Style may change further when we get voice typewriters, where our spoken words will appear on the page as they are spoken. This will relieve the memory burden. The colloquial nature may remain and even be enhanced, but—because the printed record of the speech is immediately visible—perhaps the organization will improve.
The widespread availability of computer text editors has produced other changes in writing. On the one hand, it is satisfying to be able to type your thoughts without worrying about minor typographical errors or spelling. On the other hand, you may spend less time thinking and planning. Computer text editors affect structure through their limited real estate. With a paper manuscript, you can spread the pages upon the desk, couch, wall, or floor. Large sections of the text can be examined at one time, to be reorganized and structured. If you use only the computer, then the working area (or real estate) is limited to what shows on the screen. ... The result is that corrections tend to be made locally, on what is visible. Large-scale restructuring of the material is more difficult to do, and therefore seldom gets done. Sometimes the same text appears in different parts of the manuscript, without being discovered by the writer. (To the writer, everything seems familiar.)
You can get yourself a copy of the whole book here, if you're interested:
