Natalie Tolli, a 13-year-old from Yonkers, said "it was the best time I ever had, especially seeing Justin Bieber in his red hat."
Her father, George Tolli, said he and his wife and three daughters and son waited since 2 p.m. to get their place.
"It was a pleasant surprise, very controlled," he said. "In my 51 years, I've never been here for New Year's. But I did it for the kids. And it was worth it."
In Las Vegas, fireworks were launched from eight rooftops at midnight. Police earlier shut down a four-mile section of the Strip to vehicle traffic, letting revelers party in the street. Casino nightclubs touted pricey, exclusive bashes hosted by celebrities including Kim Kardashian, Bruno Mars and Fergie.
Authorities reported only minor hiccups, including an ash tray canister fire on the 15th floor of the Paris Las Vegas hotel casino and an intermittent power outage at Bellagio that led to casino officials closing its buffet.
The Bellagio outage also affected a bank of slot machines and some guest rooms, but the problem was fixed before 8 p.m., allowing all gambling, nightclub parties and shows to go forward.
Thousands of New Year's celebrants turned out in Salt Lake City for a variety of events organized by the Downtown Alliance, while in Seattle crowds were treated to a fireworks display that included barrages from the top of the city's iconic Space Needle.
A typically busy New Year's Eve in Los Angeles became even busier as police and fire crews remained on alert for more arson attacks, after dozens of deliberately set car fires hit the city in the early morning hours of Friday and Saturday. Four suspicious car fires were reported Saturday evening.
Atlanta welcomed thousands to its downtown, where a giant peach dropped at midnight. Fireworks were launched from the top of the Space Needle in Seattle; in Houston, tens of thousands celebrated at a party with country singer Delbert McClinton.
In summer temperatures at Key West, Fla., three separate midnight drops took place. A giant facsimile of a conch shell was lowered at Sloppy Joe's Bar, Ernest Hemingway's favorite watering hole when he lived in Key West. At the Schooner Wharf Bar, the bar owner dressed as a pirate wench and dropped down from the mast of a tall sailing ship. And at the Bourbon Street Pub complex, a drag queen named Sushi descended in a glittering 6-foot red women's high heel.
The town of Eastport, Maine, lowered an 8-foot-long wooden sardine from a downtown building at midnight, in celebration of its sardine canning and fishing history.
In San Francisco, revelers lined the waterfront for the annual fireworks show.
The first worldwide celebrations started in the island nation of Samoa, which hopped across the international date line at midnight on Thursday, skipping Friday and moving instantly to Saturday.
Samoa and neighboring Tokelau lie near the dateline that zigzags vertically through the Pacific Ocean; both sets of islands decided to realign themselves this year from the Americas side of the line to the Asia side to be more in tune with key trading partners.
In Sydney, more than 1.5 million people watched the shimmering pyrotechnic display designed around the theme "Time to Dream." In London, some 250,000 people gathered to listen to Big Ben chime at the stroke of midnight. Scotland Yard reported they arrested 77 people during London's New Year's celebrations.
World leaders evoked 2011's struggles in their New Year's messages with some ambivalence.
French President Nicolas Sarkozy warned Europe's crisis is not finished and "that 2012 will be the year full of risks, but also of possibilities."
Pope Benedict XVI marked the end of 2011 with prayers of thanks and said humanity awaits the new year with apprehension but also with hope for a better future.
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