Avril Lavigne always has been considered too tomboyish to embrace the typical Tinseltown image, but after a long weekend in Vegas, it seems the punk princess finally has fallen.

Lavigne hosted the New Year’s Eve party at Prive, but the second the singer stepped into the Sin City hotspot, she went straight for the tabletop.

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"It was an Avril I’ve never seen before," a partier told Pop Tarts. "She totally let loose and was gyrating on all the couches and jumping from table to table while putting on quite the public display with her husband, Deryck [Whibley]."

Twisting and turning in her trademark T-shirt, tiara, plaid school-girl skirt and combat boots, Avril joined Lil' Jon in the DJ booth and rang in the new year by saturating the celebrators with Cristal champagne.

And even though the mini-mogul has millions to her name, Pop Tarts spotted the "Complicated" crooner sneaking out just after 1 a.m. with one of the boozy bottles beneath her arm.

Over at the Luxor’s LAX, Paris Hilton was behaving similarly as she got down and dirty on the VIP tables and at one point became so engrossed by her own dancing that she boogied up with someone new … the curtain. The "Simple" star even applied her makeup on the stage in front of the packed party house.

But this hotel heiress knows how to be a five-star host. Hilton kept the lights flashing and festivities flourishing for hours on end as she hugged her fans and tested out her tunes.

And even though the blonde bella has been hosting bashes on The Strip every night since Thursday, the Hollywood hottie was still at it on Tuesday night, partying up at the plush PURE club at Caesar’s Palace. Paris even decided to go down and drink with the average American on the dance floor well into the wee hours.

"I do get tired going out every night," Hilton told Pop Tarts. "But it's Vegas and it is a family tradition to come here over the New Year. There is no other place I would rather be, and this year is a big year in terms of work for me, so I am making the most of having a good time while I can."

Pop Tarts Talk: Hear More Star-Studded Scoops From Sin City

And despite running rumors that Leonardo DiCaprio has moved on from his model girlfriend Bar Refaeli, Pop Tarts can confirm they are very much together. We spotted them at the new club The Bank at the Bellagio Hotel on New Year's Eve sipping each other's drinks, dancing and never leaving each other’s side.

But a big week boogying in Sin City is enough to even tame the most intense Tinseltowners. Just two weeks ago, Jamie Foxx partied for a week non-stop to celebrate the big 4-0, ending the bender with a big bang at JET nightclub at The Mirage.

However, this time it was Foxx’s mom’s turn to grow a year older, and Jamie chose to celebrate with his leading lady over New Year's Eve at the Opium Lounge in Beverly Hills.

A strangely sober Foxx conversed over cocktails and dined on delicacies … but before the night was over, the Academy Award-winner made sure he took to the mic for a few songs — just to make sure everyone knew he was there.

Britney Dumped

Surprise, surprise — it seems Britney Spears' bizarre behavior has proved too much for her legal team and they have parted ways with the pop princess.

The power-punchers from the firm Trope & Trope filed resignation papers on Wednesday, with insiders at TMZ suggesting it is because Spears just didn’t listen.

Sound familiar? This isn’t the first time the Britster has been through a break-up with an attorney. In September of last year, Laura Wasser left the "Crazy" client for similar reasons of disobedience. Will our lass from Louisiana ever learn?

Is Suri Cruising Into a Hollywood Career?

She might only be 20 months old, but when your folks are two of the most famous hotties in Hollywood, it seems a life in front of the lens is destiny.

According to German newspaper B.Z, Suri Cruise, the daughter of Tom Cruise and Katie Holmes, is the first choice to take on the voice of the Berlin Zoo’s polar bear Knut in an upcoming animation project.

The furry friend earned fame when he was featured on the cover of Vanity Fair and became a children’s literary star in the book "Knut: How One Little Polar Bear Captivated the World."

And no doubt this little bear will re-captivate the world if TomKat’s kitten is cast.

"I can definitely see why they would want Suri to star," an insider close to the Cruise clan told Pop Tarts. "She has a beautiful nature and is already showing extreme talent and personality in the entertainment department. But Tom and Katie are very protective of her so I don’t know if they will want her to enter the industry just yet."

The film’s producers have not yet heard back from Suri’s agent since sending the request. If you ask us, she seems a little young for the job. Publicity stunt, anyone?

Who Is Camera Shy and Who Is Camera High?

For some stars, a new year means a new start in the media spotlight — and it turns out that Mary J. Blige definitely doesn’t mind a paparazzi pursuit.

"I feel honored that paparazzi would still bother to follow me," the hip-hopper told Pop Tarts at the opening of Jay-Z’s new club, 40/40, in Vegas on Sunday night. "That means that people are still interested in me and what I do … I have nothing to hide."

And very much like his late lover Anna Nicole Smith, Larry Birkhead is a pal of the press. While getting down at LAX nightclub, Birkhead told us that he's media-friendly and always happy to pose for pictures.

So who is either terrified or "too cool" for the cameras?

Well, Pop Tarts popped Jackson family patriarch Joe Jackson sneaking into Jay-Z’s swanky new sports bar at the Palazzo away from the press line, while Mandy Moore and Nicole Richie’s ex Adam "DJ AM" Goldstein kept their lips zipped at LAX.

Tangerine host Kevin Federline also was media shy. Gosh, we don’t even associate him with Spears — he is famous in his own right, right?

Spotted or Snapped a Star? Got a Good Scoop? E-mail poptartstips@gmail.com.