In 1989 one of the main objectives of the WWW was to be a space for sharing information. It seemed evident that it should be a space in which anyone could be creative, to which anyone could contribute. The first browser was actually a browser/editor, which allowed one to edit any page, and save it back to the web if one had access rights.
Strangely enough, the web took off very much as a publishing medium, in which people edited offline. Bizarely, they were prepared to edit the funny angle brackets of HTML source, and didn't demand a what you see is what you get editor. WWW was soon full of lots of interesting stuff, but not a space for communal design, for discource through communal authorship.
Just think now, things are being realised with wikis and blogs. But why didn't we realise this earlier on? I think the main reason isn't the technology or the idea itself, but the cost of being online, we're at a point now where most people have an always-on connection, back 5 years ago that wasn't a possibility, the idea of editing pages online would of been silly - the cost would be to prohibitive. All my first web pages were created entirely offline, it's only since about 2001 I have been creating web pages online - since I got broadband.
Just imagine where it will be in another 5 years, when we'll never be offline, no matter where we are.