Justin Bieber cadillac spago singer heart throb

Justin Bieber left dinner at Spago in Beverly Hills in a great mood ... even giving us a wave! We're lovin' that smile.

The 17-year-old "Baby" singer will be performing on The X Factor finale, according to HollywoodLife. Now WE'RE smiling, too!

Biebs' performance will include The Christmas Song" and "Santa Claus is Coming to Town from his new holiday album Under the Mistletoe. The finale will air on December 22.

Check out our video below of JB hangin' with his ladylove Selena Gomez at L.A. Live. Life is definitely good for Biebs!