Demi Lovato and Z100 jock JJ/Photo by Theo Wargo/WireImage for Clear Channel

It’s not the Christmas season until Z100 has its annual Jingle Ball. The station has, once again, lined up some of the top artists to perform at Madison Square Garden on December 9.

Z100 held the Kick Off Party Friday at Aéropostale Times Square, as Z100 afternoon jock JJ announced the official star studded line-up.

The roster includes Lady Gaga, Pitbull, LMFAO, Kelly Clarkson, David Guetta, Foster the People, Gym Class Heroes, and Demi Lovato.

The pop sensation Lovato was on hand for a special performance to usher in the Jingle Ball “season.”

“The countdown is on to Z100’s Jingle Ball ’11,” Darren Pfeffer, Jingle Ball executive producer, tells FishbowlNY. “We have assembled another historic line-up, with a few surprises in between.”

While waiting for the surprises, special guest hosts signed on for the gala concert include Kim Kardashian, Khloe Kardashian Odom, Lamar Odom, and Karmin.

Tickets are sold exclusively to Z100 VIP members at Ticketmaster starting November 1.

Mayor Bloomberg has issued a proclamation declaring December 9 Z100′s Jingle Ball Day.

For those who missed out on tickets to the Z100 holiday tradition, Jingle Ball (the concert is sold out), you’re in luck.

For the first time, the Z100 annual concert is being televised.

The star-studded show, featuring performances by Katy Perry, Enrique Iglesias, Paramore, Bruno Mars, and Selena Gomez, will be shown in HD on Fuse, Thursday, December 16 at 9 p.m.

“There’s a reason that Z100′s Jingle Ball is legendary. Anyone who’s ever attended knows that the show has an energy and excitement like no other,” says Darren Pfeffer, marketing director of Clear Channel New York and executive producer of Z100′s Jingle Ball.

Along with more than ten artists, the concert includes special guest hosts Kim Kardashian, Jay Sean, and Flo Rida.

The musical event, from Madison Square Garden, takes place on Friday, December 10.