The Web 2.0 transformation has re-written the internet stories of the mid to late 1990s. These stories have re-established the internet as priority number one for entrepreneurs and advertisers.

Perhaps the one story that got the most public attention was Google's purchase of YouTube for $1.65 billion in late 2006. The site was sold by its founders Chad Hurley and Steve Chen, just two years after they launched on a shoestring budget.

But, there's also FaceBook, MySpace, Delicious, Squidoo and many more Web 2.0 success stories.

Until recently, one thing has been lacking from these websites — advertising. When YouTube was sold to Google last year, it didn't have any advertising, neither on its pages or the videos it broadcast. And only recently has advertising begun to creep onto the pages of StumbleUpon, Delicious, Reddit and other popular Web 2.0 websites.