Users are active on Facebook and Twitter today because of the addictive nature of personally relevant content. Delicious is a library of personal links but it’s designed to showcase the vetting process of the critical mass. Social bookmarking sites of the past are missing the shift to personally relevant content, leaving a user to make use of their personal social graph on Facebook, Twitter, and Google.
The opportunity is growing for a new player who can adapt to the shifting social layer, and the demand to save and share information is stronger than ever. Niche curation will continue to thrive, as proven by incredible growth shown by Pinterest, Svpply, and BagCheck.