But why?

So Seb had some nice ideas, and said let's get everyone to write structured blogs with metadata, and everyone went yeah! that's great let's do that, it'll be semantic. So I made blam!, because I could. And then I thought, that was easy: I could make some kind of Blosqlom, that stored all the files in a database so they could have loads of keywords attached, like metadata, instead of single categories. And I could make a form that was launched by a bookmarklet from an Amazon page that you could fill your review into and it would post your review to blam! and give you the HTML with pictures and metadata and everything to post into your own weblog, where allconsuming could find it as well. And if you wanted, the form could have a search function built in that could search Amazon for the item you described, or search FreeDB, or MusicBrainz, or IMDB, or an XMLTV database, and give you the HTML to post to your weblog and post your review to blam!
But what would be the use of that? Where's the giant step for democracy? What's your automatically categorising machine learning web spider proxy going to do with that metadata that you couldn't do already with your very own mind? Bluntly, what's the point?