Occupy Wall Street gets union backing (Creative Commons).

Aaron Katersky of ABC News reports on thee ABC News blog: "Here in Foley Sq the demonstrators are streaming in via Broadway. Loudspeakers are up in the middle of the sq across from the Law and Order courthouse. No official count but the union and activist support has clearly drawn numbers...several thousand eyeballing it? All peaceful so far. A lot of signs calling for a tax on Wall St and expressing feelings of unfairness and economic injustice. 'Wall St can't you see we want a fair economy' goes one refrain. Heavy police but so far so good."

According to a tweet from @OccupyWallStNYC, there may be about 15,000 protesters at the scene. The tweet reads: "Foley Square has reached max capacity!!! At least 15k proud ralliers soon returning to #libertysquare #takewallstreet".

However, according to ABC News, NYPD estimate there are about 3,000 people in Foley Square.

The Washingotn Post's Ezra Klein writes that the Occupy Wall Street movement is at a tipping point. He reports from the protests:

Some of the people camped out Zuccotti Park for the Occupy Wall Street protest want to End the Fed. Others want to tax Wall Street. One woman assured me that “very few” of the top one percent live in New York, or even in the United States. “They’re in gated communities all around the world,” she said. Someone else saw this as a cultural revolution. When I arrived, the crowd seemed almost entirely under-30. By the time I left, it was considerably less homogenous.

There is not, in other words, all that much you can say with confidence about what Occupy Wall Street is or isn’t. At the moment, it’s different things to different people. And, depending on your perspective, that may be the nascent movement’s biggest strength or its fatal weakness.

You can watch a livestream of the protests taking place in New York below: