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THE COUNTDOWN BEGINS
One down – and nine to go! President Barack Obama and first lady Michelle salute Beyoncé after being serenaded with her rendition of "At Last" for their first dance of the evening at the Neighborhood Ball, the first of 10 balls they attended Tuesday. The first couple took their last dance of the night at the Eastern Ball after 12:35 a.m.
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THE NIGHT IS YOUNG
Tobey Maguire, Demi Moore, husband Ashton Kutcher and Rosario Dawson quadruple their fun during a group portrait at Tuesday night's Youth Ball, held at the Washington Hilton.
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After performing a surprise romantic duet together at the Inauguration's Western Ball, Marc Anthony and wife Jennifer Lopez share a laugh with Vice President Joe Biden inside the Walter E. Washington Convention Center.
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Anne Hathaway, who attended President Obama's swearing-in ceremony earlier in the day, makes a red-hot appearance at Pepsi's Creative Coalition Ball at the Harmon Center for the Arts, where she chatted up basketball great Magic Johnson.
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CHEEK TO CHEEK
Just seven more to go! The first couple continue the Inaugural festivities with a slow dance at the Commander-in-Chief Ball, where the President thanked the many members of the military in attendance for their courage and patriotism.
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Mariah Carey belts out her hit "Hero" Tuesday in honor of President Barack Obama and first lady Michelle at the Neighborhood Inaugural Ball in Washington, D.C.
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After hitting Georgetown for a little pre-Inaugural shopping with hubby Cash Warren, Jessica Alba chats up Ben Affleck at the Artist Making an Impact Pre-Inaugural dinner at L2 and Leopold's Kafe.
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DATE TO REMEMBER
A bundled up Beyoncé and her husband Jay-Z make their way through the crowd at the U.S. Capitol building in Washington, D.C., ahead of President Barack Obama's swearing-in ceremony Tuesday.
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One of Obama's most influential supporters, Oprah Winfrey, and her partner Stedman Graham greet Samuel L. Jackson at the Capitol, where they saw Obama take the oath of office Tuesday and heard Aretha Franklin sing "My Country, 'Tis of Thee."
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Diddy is feeling the love – along with mom, Janice Combs – from his prime perch at Tuesday's inauguration.
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Performing for the first-family-to-be at the Lincoln Memorial, Beyoncé delivers a powerful rendition of "America the Beautiful" on Sunday during the HBO free concert "We Are One: The Obama Inaugural Celebration".
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MEET & GREET
He's a hands-on leader! The then-President-elect greets Stevie Wonder after his soulful performance of "Higher Ground" at the Lincoln Memorial.
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Garth Brooks gets the crowd jumping with "Shout" during the concert at the Lincoln Memorial. The country superstar also sang the classic "American Pie" and paid tribute to President-elect Barack Obama with his song "We Shall Be Free."
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A bundled up Queen Latifah – also on hand at the Lincoln Memorial – puts her own frame on the historic event. Looking ahead to Tuesday's ceremony, she earlier told reporters, "I'm from Jersey, so I'm kind of prepared for the cold. I just got to keep dressing warm and lots of warm drinks hopefully will be around – lot of hot toddies."
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A HIGH POINT
The Jonas Brothers and Miley Cyrus may have been the main event – but it was Michelle Obama who got the crowd cheering at the Kids Inaugural: We Are the Future concert Monday at Washington, D.C.'s Verizon Center. The first-lady-to-be high-fived some young charges, then addressed the crowd, telling them, "You kids are the future of this great nation."
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ROCK THE VOTE
Nick, Joe and Kevin Jonas make a power trio during the kids' concert on Monday, hosted by Michelle Obama and Vice President-elect Joe Biden's wife Jill Biden. "It was awesome," Joe said of seeing the Obamas and the Bidens dancing in the front row. "I had to get them up on stage and celebrate together."
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Father-daughter duo Billy Ray and Miley Cyrus also did their part, performing at the kids' show – where Sasha and Malia Obama had a front-seat view
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ON A ROLL
Declaring the Martin Luther King Jr. holiday a day of service, President-elect Obama rolls up his sleeves – and grabs a roller – at the Sasha Bruce House, a shelter for homeless teenagers Monday.
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Also showing his commitment to service: Usher, who pitched in to make over the library at Simon Elementary School on Monday. The RampB singer teamed with MTV and ServiceNation for the "Be the Change: Live from the Inaugural" event, where he led a group of students in the project.
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CALL TO SERVICE
Ashton Kutcher and Demi Moore step right up Monday at the "A New Era of Service" breakfast at Ballou Senior High School, where they revealed a video pledging their commitment for public service. Later that day, the two also talked up their passion for volunteerism with Oprah Winfrey.
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At Sunday's Latino Inaugural Gala, Jennifer Lopez takes the stage with the next best thing: a cutout of President-elect Barack Obama. "He is the biggest star here, even though it's chock-full of celebrities," she told PEOPLE of the man of the hour.
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After shopping for vintage couture together, Jessica Alba and husband Cash Warren find a new friend in news anchor Lauren Sanchez (left) at the "Declare Yourself" event at the Renaissance Hotel. Inside the bash, Maroon 5 entertained stars like Ben Affleck and Hayden Panettiere (not pictured).
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(RAP) STAR & STRIPES
Jay-Z has one patriotic accessory – a flag! – while performing at rapper Young Jeezy's (not pictured) and Belvedere's "Presidential Status" event at D.C.'s Club Love on Sunday. The next night, the music mogul took the stage for a sold-out show of his own at the Warner Theater.