In the two years since Justin Bieber dropped his debut album, My World, the teen superstar has become one of the biggest forces in pop music and amassed a dedicated legion of Beliebers along the way.

A global superstar who can top the box office as well as the charts, it's hard to remember what pop was like pre-Bieber. Over the course of the year, MTV News watched as the young star continued to climb new career heights, and you were there as we covered every milestone on the way to Justin's becoming our #5 Top Newsmaker of 2011.

"Fans will be really excited to see that I'm just a regular 16-year-old having fun just living my dream," he told MTV News in February at the premiere of his 3-D film, "Never Say Never." "And it's possible for anyone to live theirs."

Bieber's determination to dream even bigger was clear this past year. He kicked off 2011 with the release of a concert documentary that brought fans into his world, pre- and post-fame; he followed that up with more music, dropping Never Say Never - The Remixes. By mid-year Bieber was selling out venues on his My World Tour, and at the end of '11, he was ready to celebrate the holidays with Under the Mistletoe. He also made time to rap for us right in the MTV Newsroom, had teen girls everywhere smelling good with his Someday perfume and made jaws drop by chopping off his famous locks.

"We knew it was going to be a big deal," Bieber's hairstylist, Vanessa Price, explained. "We knew it was going to shock fans, but we also knew it was going to be a change in terms of growing up. I think that's something that people adjust to."

This year was also about pushing boundaries for Bieber. He gained street cred by working with the likes of Kanye West, Chris Brown and Busta Rhymes, and when asked how he thought his music would evolve, he explained, "I'm not gonna really limit myself. I think music is music, and genre — I mean, I know there's country music, there's rock music, but my music is different. My voice is not meant for any style. I just want to make music."

The Biebs made time for love, too, spending time with girlfriend Selena Gomez at events like awards shows and on lavish date nights. And he had Gomez's support when a fan made false claims that he had fathered her child. Justin never really seemed to waver though: He shrugged off the allegations and moved on.

Bieber already has big plans for 2012. He's readying his next album, Believe, which he opened up about during his first-ever "MTV First" in October. "I'm trying to create a new sound that people aren't really used to hearing, so it might sound weird at first, but it's going to be like when Justin Timberlake did FutureSex/LoveSounds: It was a new sound ... acoustic guitar over hard drums," he explained.

"I want to find something that's going to suit me and my fans are going to love and older people will like and younger people will like. But I'm always trying to keep my core fanbase, because the young people are what make everything cool. Old people look to young people, so trying to keep everyone happy."

MTV continues our Best of 2011 coverage by looking back at the biggest pop-culture stories of the year. As we count down the newsmakers that mattered to you most, also check out our Best Artists, Best Songs, Best MTV Live Performances and Best EDM Artists of 2011.