Web 2.0 is an odd animal. Referring to sites developed for the second phase of the web, users submitting their own content. These sites both attract and repulse users. They're attractive due to their ability for users to make their mark on the web. Unfortunately, most of such content is uninteresting, stupid or offensive, which means that users are disinterested in the actual content on such websites.
Sites like these can only become successful if their interesting content is easier to find than the bad. Social networking sites do this by only showing information about your friends, who you're presumably interested in. Media sharing sites like YouTube manage this by ranking content, based on views and votes, so that searches usually reveal the gold buried inside the dross.
Web 2.0 adds a new dimension to the web, allowing users to dispense information as well as receive it, users are no longer passive observers, but actively helping expand the web. However, it's hard to tell whether this is making the web a better place, or just filling it up. Will this generation be known for improving the internet, or just be known for liking sparkling vampires?