Web 2.0 Tutorial

I recently ran across a link to a Web 2.0 tutorial for teachers. The author explains what Web 2.0 is and also discusses blogs, wikis, RSS feeds, and social bookmarks. For each of these applications, he includes lists of and/or links to popular tools of that type, educational benefits, classroom applications, concerns and solutions, real-world examples from teachers, further reading, and tutorials (including videos).