I am a big fan of the Microformats initative. From the site:

Designed for humans first and machines second, microformats are a set of simple, open data formats built upon existing and widely adopted standards. Instead of throwing away what works today, microformats intend to solve simpler problems first by adapting to current behaviors and usage patterns (e.g. XHTML, blogging).

So essentially, the idea is: if you write a review (like I did below), announce an event, post a person or job profile — do it in a standardized way, so it can be reused and aggregated. The good thing is that there are lots of editors and readers already out there. So for example you can use the Tails Firefox Extension to automatically add events mentioned on web pages to your calendar or save address cards etc. Endless possibilities of seamless data interaction.

I use the Structured Blogging Plugin for WordPress to have ready-made forms for posting reviews. For the book review, I just entered the title and it grabbed all the meta-data from Amazon. Melikes!