Here's a very new tool that promises to be more robust than Twine but easy to learn (PC only at the moment, with Mac version coming soon). https://onemorestorygames.com/write/about-storystylus/ Writers take note that there's a launch contest going on right now with $10K Canadian in prizes.

One of the most astonishing and effective structures I've seen in this format is the Twine piece "A Kiss" http://www.freeindiegam.es/2013/07/a-kiss-dan-waber/ You can view the structure of 1,001 passages (the "map" of the story) as a piece of art in itself. Navigating through the passages is a journal in time (before, during, after the kiss) and space (proximity to the characters)—brilliant. Because the fragments are highly structure in two dimensions, you regain a sense of linear progression that's often lost in hypertext. It feels orderly, no matter how you click through the piece. The story fragments, with their time/space coordinates, build on each other.

Coming from both game design and book publishing, I'd parse this further. Clicking to turn a page or further a linear narrative is one kind of interactive, passive, and in some ways forced. (Your other option is to quit.) Interactive that results in a responsive change, one that relies on user input (agency), seems like a whole different category. Navigation through a piece versus engagement in a piece. Being a reader versus being a character/player in a piece. Storytelling versus an ongoing dialogue between creator/user. I think that's critical in this medium, even beyond video games (where it's key to the experience).

Oooh, this is interesting. "Text messaging" as its own language (linguist John McWhorter wrote a great piece about this) and context, a very personal one that's disembodied and void of every other cue EXCEPT text. Eliza captured people precisely because they projected their own thoughts into a kind of unseen, blank echo chamber. Would Eliza even work (or work as well) as an avatar, like the avatar news readers or the Japanese robots whose appearance is aimed at being as realistically human as possible. I don't think so.

Wondering where data-scraped pieces fit in all this? Thinking of Jonathan Harris's We Feel Fine http://wefeelfine.org/ and similar pieces. He just released a new one that pulls key words from Twitter and other sources and aggregates them into navigable narrative snippets that are real-time and dynamic, mixed with video and audio clips. The experience is one of "story"(true ones) and could only happen electronically.... how to define? what category here would that fit in?