Yesterday, a remarkable thing happened. The comedian Dave Chappelle came to Portland, and told (by his estimate) four people he planned to show up at the downtown Pioneer Square sometime past midnight, and give a quick performance. He figured word might spread a bit, and that maybe a couple of hundred people might show up. Early in the afternoon, he fought some sound equipment to accommodate the event.

The owner of the store where he obtained the equipment promptly logged onto Twitter, and tweeted about Chapelle’s plans. Word shot around the Portland Twittersphere, and when Chappelle showed up about 1 a.m., not 200 but thousands – estimated around five to six thousand – were there to greet him. And he delivered a short show, or tried to given the technical limitations.

The remarkable thing, of course, was not Chappelle’s unusual appearance (he has a history of unpredictability) but the fact that a web of individual communications – not any form of mass media – resulted in the crowd. The story of his appearance turned up everywhere from the banner lead in the Oregonian to Huffington Post.

After the fact.

You get the sense that a page is turning.