Occupy Wall Street is a social movement (read this primer written by Ezra Klein) inspired by the Arab Spring and other protest movements around the world. Although the call to action was made by the magazine Adbusters in July of 2011, the occupation in NYC began on at Zuccotti Park September 17th, 2011. Since then, hundreds of protesters have occupied various locations in cities around the US (including Minneapolis) and the world.
Individuals in the protest movement identify themselves as the 99% and although they represent a multitude of views, they have organized around their shared interest as the 99% of people in America who do not have tremendous wealth.
In some ways they have created a new society. Food is served, medical care is provided, a newspaper has been created, and people can find reading material at the peoples library (In NYC this was all taken away on Nov 15, the city of New York claims the books are being held at an of-site location. See below).
All of this is aided in part by a unique way (or perhaps only true way) of doing democracy. Proposals for action, questions and concerns are brought forth in an organizational meeting called a General assembly. Decisions are made by consensus whereby everyone must agree. Watch this video describing the process.
The mainstream media has been critical of this movement claiming that it lacks a coherent message. More than anything this represents the fact that these activists are fed up with the traditional way of participating in democracy which they see as corrupt and ineffectual. (As evidence check out this article on Chuck Schumer) They are attempting to take democracy into their own hands and truly make it by and for the people. (read this excellent article written by anthropologist David Graeber).
A few more links:
Update: Below is a video of a UC Davis police officer pepper-spraying a group of students who were peacefully protesting the destruction of an Occupy encampment. Here is an article by Matt Taibbi that link’s the militarization of the police and to the erosion of civil liberties associated with the War on Terror.