I recently re-read his book
Literary Machines after first reading it in the late 80s, and it struck me how simultaneously visionary and impractical his ideas were. His version of the web was centralized(
), with the organisation running it covering its costs by franchising-out access points. yes, it had transclusion and versioning, but it also had rights management and automatic billing for quoting (transcluding) other people's work - all imposed by a central authority that owned the entire "web".( it had to be centralised, otherwise the contract necessary for transclusion would not work in the real world)
Nelson is a very smart visionary, but I'm glad we ended-up with the messy, decentralised web we have today.
Obligatory link to The Curse of Xanadu at Wired, back in the day: http://www.wired.com/wired/archive/3.06/xanadu.html. A real hacker nightmare story.