Web 2.0 better defined

This is a very good article that gives one more understanding of what Web 2.0 is all about.  Some of the concepts are not new, but more a realization that it is now viable to use and build.  Though the article is centered around teaching and learning it does give you an idea of what it is all about.
Social Software:blogs, wikis, trackback, podcasting, videoblogs
MicroContent: APIs, Web Services, and even Banner-ads
Openness: Flow of microcontent between domains
Folksonomy: new form of metadata - like tagging. Drawn on the "Wisdom of crowds"

The link to the article: http://www.educause.edu/apps/er/erm06/erm0621.asp