From the White House pool report:

As the world now knows, President Obama announced tonight that American forces killed Osama bin Laden in Pakistan. Transcript to follow.
After much confusion about what was happening (and where), pool was finally led into the East Room where chairs had been pushed to the side. After much waiting, press secretary Jay Carney and chief of staff Bill Daley wandered in and stood in the back–they were eventually joined by about a dozen or so White House staff. Then more formally, six top officials walked into the room and sat in a row of chairs to the side of the podium: James Clapper, Thomas Donilon, Leon Panetta, Adm. Mike Mullin, Secretary of State Hillary Clinton, and Vice President Joe Biden.
Obama walked up to the podium at 11: 36 p.m., reading from a teleprompter, and announced that bin Laden, the terrorist responsible for killing thousands of people, had been killed. The president said that Sept. 11, 2001, was “seared” into the memory of the American people. But the “worst images” were those of the empty seat at the dinner table and children without a parent. But after 9/11, people came together.
The president said he had asked Leon Panetta when he was CIA director to make the killing of bin Laden a top priority.