Reminds me of Ted Nelson's Zigzag, only he had N dimensions and a cell structure. http://xanadu.com/zigzag/
Yes, Ted Nelson has some similar work in this line. But I think he went too far with the N dimensions... Text is linear, Gingko text is 2-dimensional. With it, we can represent more than two dimensions, by simply "slicing" along any two we choose (e.g. text & comments)... not sure I'm explaining this properly :-/
I think this project is pretty cool and the idea is awesome. It would make a lot of sense on a tablet/phone and as a generalized editor.