I've been working with Jim Munroe (Everybody Dies, Guilded Youth) on developing a new kind of text game authoring system. It's called Texture, and it debuted yesterday at the WordPlay Festival in Toronto.
Stories authored with Texture are structured like books. Each scene or node is one page that has about one screenful of text. On each page under the text are some verb boxes. Dragging and dropping the verbs on the text changes the story, resulting in a sort of e-book that mutates and evolves based on the reader's interaction.
The interface is designed for touchscreen devices. It's possible to play with a mouse but dragging the verbs with a finger is the more natural way of interaction.
The writing tool looks almost the same as the resulting story, with added authoring controls.
There's very little modal difference between the reader and the writer. You write the text on the page directly and create commands by first adding some verbs and then dragging them on nouns, just like you do when you're reading the story.
The writer's user interface
steals borrows heavily from Twine 2 which I think does a lot of things right and having similar elements hopefully makes the interface easy to learn. The system itself is Jim's vision, my role is mostly on the implementation side.
When's it out, you ask? Right now! You can try the alpha version at texturewriter.com. (Disclaimer: early alpha. Not tested in IE, use Chrome or Firefox if possible. In Safari you need to save the page manually after clicking the "download" button. You may also need to try dragging the verbs twice before it responds to dropping the verb on words.)
The one major feature that's still missing is setting and reacting to flags, which would let you change the output based on earlier interaction. At the moment the system is basically stateless although not linear – you can branch the story by having different actions open different pages.