The chief evangelist for Pearltrees Oliver Starr writes:

"Humans also love to collect things — from tiny stamps to shiny cars. And what do we do with these things once we have them? We play with our collections. We organize, shape and prune them, and we display our collections for the benefit of others and the occasional bragging right. “Curation” is simply a stiff sounding word for an innate human activity — collecting, organizing and sharing — that people are now engaging in online."

Compared to creating original content, curation is even easier. (The rapid growth of Pinterest proves this pretty clearly.) And it is a deeper part of our behavior than most people realize. The fact is, all of us are curating every single day. Simply choosing an outfit is an act of curation. Although those decisions are small and personal, they aren’t that different from the decisions made by a museum curator or a newspaper editor.

More about Pearltrees: http://venturebeat.com/2010/06/24/pearltrees-funding/

Why Pearltrees believes curation is the Web's third frontier: http://www.cratyle.net/en/2010/03/11/the-webs-third-frontier/

Curation was envisioned by The Web's founders as a natural application of the medium.

Read the original proposal to develop The Web, from creators Tim Berners-Lee and Robert Cailliau in November 1990.

Note the way its creators describe The Web and it's applications in their proposal.