Outpouring over Michael Jackson unlike anything since Princess Di

Since news of Michael Jackson's passing, there has been an emotional outpouring not seen perhaps since Princess Diana's death in 1997.

The 24-hour news cycle and social media are probably amplifying the reaction. But the response seems genuinely broad and intense – which may be surprising given the pop star's transformation into something of a bizarre and controversial recluse in his last 20 years.

If the death of a pop star was to be measured by tweets alone, Michael Jackson's would seem to be of monumental importance. About 15 percent of Twitter posts mentioned Jackson when the news broke Thursday evening, noted Harvard researcher Ethan Zuckerman in one tweet, comparing that with hot topics such as Iran and swine flu that never crossed 5 percent.

By Friday afternoon, 9 of the top 10 albums selling on iTunes were Michael Jackson's, Amazon.com had sold out all his CDs, and major retailers coast to coast were running out of his music. Online, Facebook and news websites were swamped with tributes. And Fans gathered across the world, from a mass moonwalk in London to tributes on the Walk of Fame in Los Angeles to vigils in Paris and Tokyo.

The overriding reason is his extraordinary musical influence.

"The reason you are seeing this global outpouring of interest is that Michael Jackson is singular in the history of pop culture. No one even comes close," says Professor James Peterson at Bucknell University in Lewisburg, Pa., who teaches hip-hop culture, African-American literature, and sociolinguistics. Mr. Peterson points out that Jackson's achievement of 750 million in global album sales will never again be equaled because of the absolute change in the music business caused by the Internet.

Besides having had a dramatic influence on such artists as Usher, Chris Brown, and Justin Timberlake, Jackson "at once captures and encapsulates the history of blacks in dance. Any number of popular artists could not exist at the level they have without Michael Jackson," says Mr. Peterson.

For some, Jackson's body of work may trump all the other questionable aspects of his lifestyle – the child molestation charges, facial alteration, and reclusiveness.

"There have been at least three generations of listeners – one for each of his musical incarnations," Peterson notes, adding that he has a 10-year-old son who is now getting immersed in Jackson watching Peterson and his wife in mourning. "A fourth generation of followers is going to emerge because of this," he says.

Jackson was also one of the few musicians to transcend narrow ideas about how a black man should look and act and reach a global audience, says Professor Jeff Melnick, who teaches African American studies and popular culture at Babson College in Wellesley, Mass.

But the intense response to Jackson's death also reveals society's deep investment in celebrity culture worldwide, he says, adding that there is an acknowledgement that the demands of celebrity culture wounded Jackson from the moment he hit the scene as a boy in the late 1960s.

"The outpouring is partly guilt, then – it is a confession of sorts," says Mr. Melnick, "of the culpability of the fan in the premature death of the artist."

With virtually no offstage in his life, "Jackson became a canvas on which fans projected all kinds of fantasies – about proper gender behavior, about racial norms and what we should do with our bodies."

Jackson also gave more than $300 million over the course of his life to charities all over the world, which may have something to do with tributes coming from several world leaders, from Britain's Gordon Brown to former president of South Korea Kim Dae-jung and South Africa's Nelson Mandela.

Other cultural anthropologists and researchers suggest the current economic downturn has accelerated global notions of nostalgia.

"We mourn the loss of ourselves through this pop icon," says Tracy Johnson, Research Director of Context-Based Research Group which studies consumer behavior.

"We recognize that we, particularly in America, have lost a little bit of what we were all about," she says. "Someone like Michael Jackson who so embodied the American Dream just makes that loss all that much more palpable."

Above all, it was his music and unique, energetic performance style that attracted fans around the world.

"One reason Michael Jackson's death is having such a wide impact is because his music had such a wide, and even sustained impact," says John Covach, a music historian at the University of Rochester. "Few artists have so completely saturated the market as Jackson did during the 1980s. It's comparable to the Beatles in the 60s or Elvis in the 50s. When an artist or performer is so well known and loved, the reaction to his or her passing is bound to be strong and widespread."

"One important difference between Jackson's career and those of many others is that he was a child star who became an adult star – a very difficult transition to pull off," says Professor Covach. "Even those who were too young to be fans of Jackson when he was a child have seen the clips of him performing with a mastery far beyond his years. The adult Michael Jackson that fans loved in the 1980s thus already had a bit of history – people felt like they knew him already."

And so, people from around the world continue to talk with friends and strangers about this musical legend, their voices spread more widely by new means of communication.

In the hours after Jackson's passing, AOL's instant messaging service was down for 40 minutes due to an increase in traffic. In a statement, AOL also noted that, "Today was a seminal moment in Internet history. We've never seen anything like it in terms of scope or depth."

As if to connect the two major icons of celebrity lost in recent years, the Telegraph in London reports that Harrods owner Mohamed Fayed has announced that he will erect a Michael Jackson Memorial at the store to join the one of his late son, Dodi and Diana, Princess of Wales.