Prior to reading these articles, I had never heard the term "Web 2.0" before. It seemed pretty self explanatory to me - a newer, better version of the internet. After reading the articles, I am a bit more confused than I was before, however I still found them interseting. I had no idea there were so many specific things that had been replaced, as I had never really thought about what the internet was like before Web 2.0 (past more sophisticated capablilities/design). In What is Web 2.0 , O'Reilly explores the key differences between the internet now, and Web 1.0. He thouroughly explains concepts such as the Web as Platform, Harnessing Collective Intelligence, Rich User Experiences, and more.
In Web Squared: Web 2.0 Five Years On , O'Reilly and Battelle reflect on their original analysis of Web 2.0 and how the internet has since further evolved. I was most confused by the section where they discuss Photosynth, but I think the section Web Meets World rather makes a lot of sense. I also enjoyed reading the last section, A Call for Examples, where O'Reilly and Battelle closed off their paper with a call for input/action.