TORONTO - For smitten Justin Bieber fans, a 140-character Twitter message from the mop-topped heartthrob is the equivalent of a bouquet from their beloved.

So when the 16-year-old Stratford, Ont., native interacts directly with his teenage fans, it's an experience they don't soon forget.

"He wrote to me once," said 14-year-old Brittany Collins of Oshawa, Ont. "I got really excited. I saved it and put it on Facebook. I was so happy. I couldn't believe he actually did it."

She waits a second, then beams.

"He follows me."

For generations, teenybopper performers have sent young hearts aflutter, from the Bay City Rollers, to Shaun Cassidy, to the New Kids on the Block and the Jonas Brothers. But experts note those performers have never communicated with their fans as directly as the social media-savvy Bieber. And that's helping to build his massive hype.

By occasionally reciprocating the attention that's heaped onto him by his leagues of admirers, Bieber is only increasing his disciples' devotion -- 140 characters at a time.

"I think he is up there with the very biggest music phenomenons of all time," said Brad Schwartz, senior vice-president and general manager for Much MTV Group.

"I would never in a million years compare Justin Bieber to the Beatles, but you look at some old video of the Beatles getting off a plane in an airport, and you compare that to the video of Justin Bieber in (New Zealand) -- I don't want to compare the two but the phenomenon around Justin Bieber seems to be as big as any of all time."

Schwartz is referring to the mob scene that greeted Bieber during an April trip to Australia and New Zealand. His public performance in Sydney was shut down by police after thousands of fans surged toward stage barriers and eight girls were sent to hospital.

Soon afterward, he arrived in Auckland, where overzealous fans knocked over his mother, Pattie Mallette, and stole his hat. These incidents followed aborted appearances at malls in Long Island, N.Y., and Paris, with reports of out-of-control crowds again making the news.

In Toronto, Collins was among hundreds of fans who carved out spots outside MuchMusic headquarters in downtown Toronto last week with the goal of securing a pass for Sunday's MuchMusic Video Awards.

For many, braving a few humid nights camped out on Toronto pavement was a small price to pay for the chance to interact with the cluster of stars promised for the weekend's festivities: Drake, Adam Lambert and, of course, Bieber -- the artist most likely to set the throngs a-shrieking at Sunday's streetside bash.

That devotion to Bieber extends to the online world, where he's constantly talked about on Twitter and has been referenced as many as 125,000 times daily, according to data supplied by Trendrr, a real-time social and digital media tracking agency.

Many even believe that Twitter adjusted its algorithms specifically to put an end to Bieber's dominance in the trending topics section of the website. Now, trending topics are defined as topics that are immediately popular, rather than topics that have been popular for a while.

Crafty Bieber fans then began tweeting about "Bustin Jieber" as an act of protest, and soon that too was trending.

"I would say that Justin Bieber is conceivably the biggest legitimately monetized social media phenomenon of our time," said Simon Dumenco, a media columnist for Advertising Age magazine.

One of the primary reasons Bieber's name had claimed a perpetual spot among the trending topics is that millions of girls are constantly writing to him in the hopes that he might return the favour.

Late Monday night, Bieber responded to a series of fans in a matter of minutes, retweeting messages from users with handles including "biebercrazy83," "BieberOnAir" and "BoJaNa--LoVeS--JB." Many of the messages were from users lamenting the fact that Bieber had never noticed them (sample tweet: "i wonder if @justinbieber ever sees my tweets, probably not, but im never gonna stop trying<3").

He even follows some of his fans -- more than 70,000 of the 3.1 million-plus who follow him. It might not seem like a particularly even ratio, but he commits to more than most celebrities do. Consider Ashton Kutcher, who follows 568 people out of the more than 5 million who subscribe to his feed, or Conan O'Brien, who has more than 1 million followers and only follows one person.

"It becomes like a lottery," Dumenco said. "Where (if they're) a dedicated fan, if they jump up and down on Twitter enough and say enough things about Justin Bieber, then you luck out and he'll follow you back, and you're one of the lucky few.

"And by that, I mean one of the 70,000."

Bieber's tweets are part of what separates him from his teen-idol predecessors, who ignited a screaming ruckus whenever they appeared in public but never so thoroughly created the illusion of reciprocating their fans' feelings.

"(His tweeting) is a marketing modus operandi, but I do believe this is somebody who's invested in Twitter because he likes those little 140-character updates," Dumenco said.

Greg Elmer, professor of media studies at Ryerson University, said the relationship between Bieber and his fans isn't completely synthetic, since they do interact at concerts, signings and on Twitter.

"Fans are feeling as though they're getting some kind of special attention," Elmer said, although he added that Bieber's fan interactions are obviously orchestrated for maximum effect.

"Is it a real friendship? Is it a real intimate relationship? No. So, I think, not to sound cynical, but it is part of marketing culture. It's part of selling personalities, and selling CDs, and programs, and popular culture."

But ask Bieber's adoring fans and they'll say they love him because he seems so real.

"I like him because he's really just down to earth," says 16-year-old Emily Isabelle, a Torontonian who lined up for MMVA tickets last week.

"He isn't like those goody-two-shoes people. He acts like a 16-year-old guy, he doesn't act like he's 13, like the Jonas Brothers.

"He really cares a lot for his fans."

And she would know. After all, she communicates with Bieber every single day.

"Oh, definitely. I follow him on Twitter, I follow him on Facebook," she says.

"I don't have MySpace, but I should get it -- just to follow him."