The Memex Revisited

So I was thinking more about random stuff...hey I do that a lot, but what would happen if someone made something like a tagging site, but was not constricted to the barriers of using simple language to show relationships.

What would happen if there was a site where one could not only tag stuff like delicious and select trusted sources for different ideas or groups like Yahoo! MyWeb, but also be able to connect ideas using more than just a common word tag...

ie: the system could

• passively archive shared information supply and relationships like Google search (to use as a backfill of your experiences)

• passively archive stuff you have seen like Google Desktop (to use as a backfill of your experiences)
• actively archive stuff you trust or like more
• let you annotate why something is important AND how it relates to other things that were annotation worthy (this would allow you to tag many ideas together, even if their relationship was harder to explain than what is allowed by a simple tag with a single word or two)
• track when you first saw something, when you revisited it, and how often you visit it (with giving you the ability to select or hide this information)
• let you track when content has been revised, showing current versions and giving you the option to quickly see what has been added, removed, or changed
• track when an idea or document or experience superseded a past one (and give you the ability to select or hide this information)

No, this idea is not my idea, it is Vannevar Bush's idea (from the 1930's and well explained in As We May Think).

I am just wonder what is stopping someone from making a true Memex device. Is it still too cost prohibitive? Is it the lack of monetization model for quality publishers? Is it a feared death for publishing houses? Is it because we sometimes enjoy forgetting some of the things we have seen or done? How do you get past all that? And should we?