Well, it's simple.  Most poems and stories I have seen on the internet are essentially postings of stories that could be written on paper.  But hypertext gives you a flexibility that is impossible with conventional writing media.  It is my belief that we are at the dawn of a whole new form of writing...a kind of three dimensional writing where you can go forward, backward, up a level or down a level.  One can change points of perspective with the click of a mouse.   The reader will have the power to read a story multiple ways. Therefore, the tone of a story would depend on the reader as well as the writer.