Julian Bond comments to my rant about ENT:

Strange, Paolo, I don't see any categories, ENTs or tags in your blog or in your RSS. Implement man, implement!

Actually we did implement. I regulary add ENT tags to all posts on my company weblog, but I don't do on this weblog anymore. We did publish ENT topics with all posts for a while, during the W4 test (for example, check out this archive page of one year ago). 

With the public W4 beta we run a public aggregator for more than one year and we collected hundreds of thousands of posts. The W4 site was aggregating posts from a couple of hundreds of feeds, organizing them with the topics created by our beta-testers, in other words 20 "active" bloggers were tagging their own content while the rest of the feeds were automatically tagged by our engine using tags created by active users.

But K-Collector is a tool designed for internal usage and we decided to stop aggregating content on W4: we didn't have the resources to increase its size and anyway it wasn't our business.

But this does look like Technorati's business, they have the resources, a team of very smart people and could gain the momentum to make a difference.

But Julian makes a very good point, I will start adding tags to my weblog right away. Actually I have a very cool tool to do it :-)