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WHAT A FIRECRACKER!
From Vegas to Miami, Molly Sims lets sparks fly at Blade nightclub in the Fontainebleau Hotel.
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NEW YEAR'S KISS
Meanwhile, at Miami's Mansion, Lindsay Lohan nabs a smooch from girlfriend deejay Samantha Ronson.
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Below-freezing weather? Who cares! The Jonas Brothers keep the party going in New York's Times Square, ringing in the new year with (from left) Taylor Swift, Lionel Richie, Ryan Seacrest and Demi Lovato for Dick Clark's New Year's Rockin' Eve.
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In Las Vegas, Heidi Montag and Spencer Pratt toot their own horns from a booth at Christian Audigier the Nightclub at Treasure Island Hotel and Casino. The couple hosted the bash while sipping Dom Perignon Champagne and eating chocolate-covered strawberries.
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Fergie, in an Ina Soltani feathered minidress, counts down to 2009 atop the catwalk at Las Vegas club Lavo. After the clock struck 12, she got a New Year's kiss – from soon-to-be husband Josh Duhamel. The two are set to wed Jan. 10.
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ICING ON THE CAKE
After a rooftop champagne toast, a newly blonde Ashlee Simpson-Wentz gets sweet on husband Pete Wentz while hosting the festivities at Pure nightclub in Las Vegas. The two later retreated inside to their VIP table for cocktails and dancing.
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PEOPLE's Hottest Bachelor Mario Lopez suits up for a New York-style New Year's Eve at Marquee.
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With the power of three, Khloe, Kim and Kortney Kardashian toast 2009 as the hostesses with the mostest at LAX nightclub in Las Vegas.
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Usher and wife Tameka Foster share a money night at The Bank nightclub inside the Bellagio. Fans also got bang for their buck: The RampB star took took over the deejay booth and performed his hits including "Love in This Club," "Bad Girl" and "Yeah."
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BOYS' NIGHT OUT
Also in Vegas: A couple of New Kids on the Block, Donnie Wahlberg and Danny Wood, who partied at Jet nightclub inside the Mirage.
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NEW YEAR'S DATE
Longtime couple Nick Lachey and Vanessa Minnillo make it a couple's night in Miami, snuggling up at LIV nightclub inside the Fontainebleau Hotel.