From OccupyWallStreet.org

Our Mission
On the 17th of September, we want to see 20,000 people to flood into lower Manhattan, set up beds, kitchens, peaceful barricades and occupy Wall Street for a few months.

Like our brothers and sisters in Egypt, Greece, Spain, and Iceland, we plan to use the revolutionary Arab Spring tactic of mass occupation to restore democracy in America. We also encourage the use of nonviolence to achieve our ends and maximize the safety of all participants.

Who is Occupy Wall Street?
Occupy Wall Street is leaderless resistance movement with people of many colors, genders and political persuasions. The one thing we all have in common is that We Are The 99% that will no longer tolerate the greed and corruption of the 1%.

The original call for this occupation was published by Adbusters in July; since then, many individuals across the country have stepped up to organize this event, such as the people of the NYC General Assembly and US Day of Rage. There'll also be similar occupations in the near future such as October2011 in Freedom Plaza, Washington D.C.