South Korean pop sensation Psy's "Gangnam Style" has become the most-viewed YouTube video of all time, with the infectious music video approaching 1 billion views worldwide.

The wildfire popularity of the four-minute song and dance video, uploaded just six months ago, represents an inflection point for the online video site, as YouTube's entertainment offerings expand beyond candid homemade videos such as "Charlie Bit My Finger" or such made-for-TV moments as Susan Boyle's "I Dreamed a Dream" performance from the show "Britain's Got Talent."

Some of the most popular videos of 2012 were created exclusively for the Web -- with musicians, comedians and even a San Diego-based human rights organization, Invisible Children, taking advantage of YouTube's global reach to attract millions of viewers.

"It definitely suggests that there's change afoot," said James McQuivey, an analyst with Forrester Research. "I don't think the change is about one form of entertainment replacing the other. It's about the expansion of the platform to include more things. That will continue."

YouTube now attracts more than 800 million users, who watch more than 4 billion hours of video a month on YouTube. The viral nature of "Gangnam Style" -- which spread from Asia to the United States to Europe -- illustrates the power of the Internet to influence popular culture.

"A lot of people are used to us having an insular pop culture, where everything is originating out of the U.S. and spreads to other parts of he world," YouTube trends manager Kevin Allocca said. "YouTube is a global thing -- 70% of YouTube's views happen outside of the U.S. You have these things that are phenomena at a global scale."

Invisible Children used YouTube's global platform to bring attention to a brutal leader in central Africa, Joseph Kony of the Lord's Resistance Army, which kidnapped children and turned them into sex slaves and boy soldiers for more than a century. The "Kony 2012" video, which some criticized for oversimplifying and distorting the story, set a record for attracting the most views on YouTube in a single day -- 31 million. Stars including Rihanna, Justin Bieber and Oprah helped promote the documentary -- which provoked a response from the United Nations Security Council.

"One of the most popular audiences of that video was 13- to 17-year-old girls," Allocca said. "Think of how strange that is: a 30-minute documentary about a warlord in Africa being popular with 13- to 17-year-old girls."

One father's response to his daughter's Facebook post, in which she complained about her parents and doing chores -- and he reacted by firing multiple shots into her laptop -- attracted some 11 million views in a single day, and has logged more than 35 million views to date.

"That created a massive amount of controversy and discussion.... It became this whole conversation, where everybody wanted to weigh in," Allocca said. "Social media is such an essential part of our lives now. That was not a problem five years ago, where you had to deal with your daughter on Facebook."