From MSNBC:

U.S. officials who had seen the entire tape told NBC News that in the tape, which they said was authentic, bin Laden tells the American people that “Bush cannot protect you.” They said there was no plan to raise the terrorist threat level, currently at yellow, or “elevated,” because it makes no specific threat. Neither the Qatar-based channel nor U.S. officials would say how it had received the tape.

FOX:

Multiple sources told FOX News that the 18-minute videotape is authentic and said its release was timed to coincide with Tuesday's presidential elections. Bin Laden makes reference to recent conflicts in Iraq and addresses the American people directly, sources said. U.S. officials said the tape appears to have been made recently. Bin Laden is speaking from a lectern and he talks about threats to the United States and he says that President Bush will not protect the American people.

UPDATE:
Still waiting on a full transcript/translation...

AP: Al-Jazeera Airs Videotape by Bin Laden

The Arab television station Al-Jazeera aired a video of Osama bin Laden on Friday directly admitting for the first time that he carried out the Sept. 11 attacks and promising to outline "the best way to avoid another Manhattan."

It was the first footage of the al-Qaida leader to surface in more than a year. The video showed bin Laden in traditional white robes, a turban and a cloak reading from papers and standing in front of a plain, brown cloth background.

"We decided to destroy towers in America," bin Laden said.

He said the attack was carried out because "we are a free people ... and we want to regain the freedom of our nation."

He also accused President Bush of "misleading" the American people three years since the 2001 suicide airline hijackings that hit the World Trade Center towers and the Pentagon.

UPDATE:
Al-Jazeera says that they have subtitled the tape and will be making it available on their web site soon.

More from al Jazeera:

In an address just days ahead of the US presidential election, bin Ladin also said the US administration resembled "corrupt" Arab governments.

He accused Bush of reacting slowly to the September 11 attacks, saying: "I never thought that the supreme leader would leave 50,000 of his people in the two towers to face the terrifying events alone at the time they were in need for him."

Refering to next week's elections, he told Americans: "Your security is not in the hands of (Democratic candidate John) Kerry or (President George W.) Bush or al-Qaida. Your security is in your own hands ...."

He accused Bush of "misleading" the American people four years after the September 11 attacks.

Claiming responsibility for the attacks, bin Ladin said, "we decided to destroy towers in America," because "we want to regain the freedom of our nation."

He added that "the reasons to repeat what happened" on 11 September 2001 remain.