SEOUL, April 13 (Reuters) - Hips swinging, South Korean rapper Psy launched the dance and video of his new song "Gentleman" at a packed Seoul concert on Saturday, with nearly 160,000 tuned in online to see if he could carry off a repeat of his megahit "Gangnam Style".
The video for "Gangnam Style" is the most watched ever on YouTube with more than 1.5 billion hits, and its horse-riding dance has been imitated by thousands around the world, from Eton schoolboys, to U.N. Secretary-General Ban Ki-moon.
But a recent challenge from the "Harlem Shake" global dance craze upped the ante for "Gentleman", and the 35-year-old Psy has made it clear he was aware of the high expectations.
"Of course I feel more burden than before, because lots of people are watching," he told a news conference before the concert. "(Today's show) is a performance of thanks for the 'Gangnam Style' success."
The video for "Gentleman", whose refrain is "I'm a mother father gentleman", featured a fast, hip-swinging dance by Psy in his trademark sunglasses and a variety of jackets, from baby blue to hot pink and sparkly white.
Fans, many of them dressed in white as Psy had requested before the concert, packed the 50,000 seats at Seoul's World Cup Stadium. The concert was also streamed live on the Internet.
"Gentleman", released on Friday at midnight, had more than 1.2 million hits on YouTube for the song alone before the concert. It was 90th on the Apple iTunes store chart.
"I thought it was really good, really funny. It is hard to compare with the classic though. 'Gangnam Style' is perfect," said Mark McKeon, a 25-year-old English teacher at the concert, who said he thought the new song still would do well.
Others said the video helped. "When I listened to just the song, it wasn't good, but it is now okay with lots of dancers dancing together," tweeted one Korean man.
Psy, whose real name is Park Jae-sang, graduated from Berklee College of Music in the United States but had a rocky decade in show business before "Gangnam Style" rocketed him to global fame.
His debut 2001 album, "Psy from the Psycho World", ran into trouble with the authorities for "inappropriate content" in the lead song, which was seen as sexually suggestive. He was charged with possession of marijuana in 2002.
He released five more albums.
Psy's brash style - at Saturday's concert, he danced to a Beyonce song in a skimpy bodysuit - contrasts sharply with the polished stars that dominate K-pop, an increasing presence on the world stage.
A Music Industry White Paper published by the Korean Creative Content Agency said sales of K-pop outside Korea surged 135 percent in 2011 to $196 million. In 2006, overseas sales were worth $16.7 million.
"Gangnam Style" racked up 3.59 million digital sales in the United States and Canada last year, according to Nielsen SoundScan and Nielsen BDS, ninth in the best-selling list. It was third on Amazon's MP3 song bestseller list for 2012.
But it has been challenged by "Harlem Shake", an electronic dance track by DJ Baauer released last year that went viral as a YouTube craze after Australian teenagers posted their version of the dance, sparking thousands of imitations. (Editing by Jon Hemming)