In the short note “The Problem with Metaphors” in Dream Machines, Ted Nelson writes:
“…a bunch of windows on the screen is called a “desktop metaphor”, since it looks to some people like paper on a desk. […]What matters is the best way to detail the virtuality, not finding a relationship to anything that came before. The best new virtualities will have no antecedents.” (p.69)
In 2005 Peter Morville unmasks the Navigaton metaphor* on the web as limiting and counterproductive in his book Ambient Findability. There is “no there there” and thats why there is no sense in drawing a map the web. Web maps are popular as subway map style posters or as interactive dots connected with thin lines in the form of a flash animation. But they do not give more than pretty pictures.
“The exploration of new metaphors and the courage to design beyond metaphor are both critical in innovation in web design.” (p.38)
* Morville mentions a research from 1998: Metaphors We Surf the Web By (PDF) by P. Maglio and T. Matlock. Back then, in hope for more spatially rich navigation experience, they concluded : “Both experienced and unexperienced users talk about the web as if they are moving toward information, rather than as if information is moving toward them. […] The trick lies in discovering the conceptual differences between real space and cyberspace, and then in using those differences to make the boundary apparent.”