33. Demi Lovato - Demi has had a tough year, but we at Hollywire are standing by her!

We are happy to see her taking care of business now instead of when it's too late!

Demi is a talented artist and we can't wait for her new album! Get well soon!

17. Ashley Tisdale - Ashley's taken her career in a variety of directions and we couldn't be more proud!

From 'High School Musical' to 'Country Strong' and the 'Hellcats' cheerleading captain,

Ashely has proven her ability to move quickly and freely through so many different characters; it's nice to see that she didn't get type-casted!

16. Miley Cyrus - Miley has had a breakout year.

She finished up 'Hannah Montana,' and broke out on the music scene as the girl who “can’t be tamed.”

Keeping it lively we've learned there’s never a shortage of anything to report on with Miley!

14. Zac Efron - Earlier this year Zac made us fall in love all over again with his lead role in 'Charlie St. Cloud'.

His charm and that smile make us so glad to have him back on the big screen!

13. Lady Gaga - A pop culture music icon who is not afraid to push the envelope on stage, on the streets, or in life!

She is one of Hollywire’s favorites because of her fearlessness to be whomever she wants! Little Monsters unite!

12. Usher - We love Usher because he's just so smooth!

He had a killer year with his hits "OMG" (featuring will.i.am) and "DJ Got Us Fallin' In Love" (featuring Pitbull),

and came out with his sixth album 'Raymond v. Raymond.'

Plus he discovered our #1 favorite of 2010 (hint hint)!!!

6. Rihanna - Rihanna has had a good year!

"Love The Way You Lie" hit number one on the Billboard Hot 100 list this year, making it her fifth!

She is fearless in fashion and exudes sex appeal!

5. Cast of Harry Potter -

Daniel Radcliffe, Emma Watson, Rupert Grint

The Harry Potter Book series took the world by storm when they first came out and then when the books were made into movies it just elevated it all to a whole new level!

Never have we seen such a long-running book turned movie series that kept its fan-base, and actually gained more as the years went by.

The cast of Harry Potter will go on to do amazing things and we will miss them as their signature characters.

4. Katy Perry - Katy Perry exploded on the music scene in 2008 with the racy but catchy hit single, “I Kissed A Girl.”

And life has only gotten better since then! Performing and presenting at the Grammy Awards and at the Victoria’s Secret fashion show.

Oh, and she married the adorably, hilarious British actor/comedian Russell Brand (#37 on our list)!

We heart you Katy! Keep the albums coming!

2. Selena Gomez - This Disney star is everywhere!

She is a multi-talented actress and we will definitely be seeing more of her in the years to come!

She's got style like not many others her age and almost always makes it on our best dressed lists...that's a good thing, since she just launched her own clothing line earlier this year too!

1. Justin Bieber - Justin Bieber’s amazing success story and adorable charm helped to put him at the top of our list!

Justin has 4 of the top 10 most-viewed Youtube videos of 2010 and his video 'Baby,' featuring Ludacris, is still the number one most-watched video on Youtube of all time!

Oh yeah! Bieber Fever is here to stay!