Wa-ay back in 2002, Paul Ford wrote an article gazing into the future. He speculated that Google would beat Amazon and Ebay to the Semantic Web.
He suggested that:
in late 2004, with little fanfare, Google introduced three services, Google Marketplace Search, Google Personal Agent, and Google Verification Manager, and a software product, Google Marketplace Manager.
Well, it turns out that Google are pretty much following that model, and in pretty much the timescale suggested give or take a bit. There latest offering at base.google.com [warning: this seems to be slipping in and out of alpha at the moment - so it may not be there...] seems to go someway in this direction.
Note that the Google Verification Manager would go some way to addressing the issue of Identity, which was the first item of Marc Canter's list of future trends to watch...
Paul Ford then went on to talk about a few other things including web-savvy spreadsheets.
spreadsheets are important to the future of the Internet. Not the gunky ones we have now, but super-futuristic ultra-spreadsheets. Say I wanted to sell my books, and put an ISBN number into a spreadsheet, and then applied a Semantic Web-based function. So I have ISBN 2884838483, and I enter item.book.isbn(2884838483) as the function. This goes out talks to the Library of Congress, which spits back a nice MARC record, and an XSLT script converts that an RDF descriptions according to the Open Products Hierarchy, and fills in title, author, publisher, number of pages, just like that in the spreadsheet. And each of those items can be related to other information, because there's a standard way to define data interchange (XML) and the actual structure of the data (RDF).
Web-as-spreadsheet is fun to think about, I swear.