One of the ways people can organise information better and help others search for it is by using tags. Meta data can help solve many problems related to semantics and appears to be a easy way to avoid more formal ontology matching which has its own problems. Things are heating up in the semantic web (SW) with lot of people coming up with new ideas to use the semantic web(SW). I recently had a few good discussions on the semantic web mailing list maintained by w3c. I found a rather nice use of the semantics in encoding for database compression and security. You can download the whitepaper at about semantic encoding in databases at the above link.
Ps: I deceied to tag my posts...:)
Tags: Semantic Web, Databases, Web 2.0