This article was disappointing. I thought he was going to identify the salient features of writing designed for the web. Hopefully he will in his talk.
No good writing is ever designed past a point. Novelists, essayists, journalists, all have a distinct style. Most of them break all the rules there are. Online, there's an even huger difference, even in similar fields. Jason Kottke versus Andy Baio. FiveThirtyEight versus Andrew Sullivan. Nobody sounds the same. That's the point.
Do you want Copyblogger? "Make bullet points, bold words to emphasize, write short paragraphs, include five links in every sentence, include a picture of a naked woman with lolspeak written above?" Because all you'll learn is that there's no such thing as a "salient feature" of writing. There's writing, and different people do different things, and some people like certain kinds of writing more than other. Some people write paragraphs with a few hundred sentences, and people read their stuff because it's good. Other people write in very sparse shorthand. It's all allowed, and it's often all good.
http://faculty.vassar.edu/mijoyce/
http://en.wikipedia.org/wiki/Afternoon:_a_story
I think you could consider this a use of hyperlinking before the web. And if you count "As We May Think", then it is a use way before the web.
It is certainly very different from a usual novel. For starters you have no idea how long it is. Hyperlinks aren't highlighted as we've come to expect and so I have to admit that I was doing some Myst-style random clicking at times. You'll often get back to the same paragraph but through a different path, these paragraphs are usually written in such a way that they would make sense by any path that you'd arrived at them.