"Stunning, beautiful," said Cinthya Romo, 32, a Sydney-based interpreter from Chile who watched the 12-minute fireworks show from the Opera House.
New Zealand and many South Pacific island nations were first to see in new year.
In the biggest city in New Zealand, Auckland, explosions of red, gold and white burst over the Sky Tower while tens of thousands shouted, danced and sang in the streets below.
As the clock ticked closer to 2011, cities across Asia readied for midnight events ranging from traditional prayers in Japan to a massive pyrotechnic display in the shape of a dragon in Taiwan. Europeans were looking forward to celebrations that could help them forget their economic worries.
- Hundreds of thousands of people gathered along Hong Kong's Victoria Harbor to watch fireworks explode from the roofs of 10 of the city's most famous buildings.
- At Japan's Zojoji temple in central Tokyo, founded in 1393, monks chanted as thousands packed in to count down until midnight. Revelers released a mass of silver balloons carrying notes with their hopes for the future, as the temple's giant 15-ton bell rang in the background.
- In New York City, nearly a million revelers were expected to cram into the streets around Times Square to watch the traditional midnight ball drop.
- This year marks the first time Vietnam's capital, Hanoi, officially celebrates the new year with a countdown blowout, complete with a light show and foreign DJs in front of the city's elegant French colonial-style opera house.
- At midnight in Taipei, Taiwan, fireworks formed a spiraling dragon climbing up the city's tallest skyscraper.
- In the Philippines, powerful firecrackers have injured at least 245 people in recent days and Health Secretary Enrique Ona urged safety during Friday's celebrations, saying he feared up to 1,000 injuries.
The Associated Press contributed to this report