Come on...He's John Mayer...we knew it wouldn't last forever!

"Life & Style" magazine claims that JOHN MAYER is cheating on KATY PERRY, and has been from the start! 

Supposedly, he has a "sex buddy" he's been seeing for two years and he's still seeing her!

A source says, quote, "They meet frequently, just for sex dates.  And they sext each other almost constantly."

If you're going to see Madonna...DON'T SMOKE!

MADONNA freaked out on a fan before her concert in Chile Wednesday night . . . because they were smoking a cigarette during her sound check.  It was an open-air theater, and apparently some smoke blew up in Madonna's face.

She yelled, quote, "[Someone is] smoking right now.  No smoking! . . . If you're going to smoke cigarettes, I'm not doing a show.  [Eff] you.  If you don't care about me, I don't care about you.  All right, you wanna play that game?

"I'm not kidding.  I can't sing if you smoke . . . if you love me, then don't smoke . . . you're looking right at me, and you're smoking cigarettes, like I'm a stupid [effing] idiot."  She stormed off the stage . . . but the show later went on as planned.

Lots of CHRISTMAS on TV this weekend!

Tonight:

"Michael Bublé Christmas Special" . . . 8:00 to 9:00 P.M. on NBC.  Rod Stewart, Blake Shelton andCarly Rae Jepsen are among the performers. 

"Christmas in Washington 2012" . . . 8:00 to 9:00 P.M. on TNT.  Diana Ross, Demi Lovato, Megan Hilty,Psy, Scotty McCreery and Chris Mann perform.  Conan O'Brien is your host.

"Christmas with the Mormon Tabernacle Choir" . . . 8:00 to 9:00 P.M. on PBS.  Jane Seymour and baritone Nathan Gunn perform with the choir.  

"Grandma Got Run Over by a Reindeer" . . . 9:00 to 10:00 P.M. on the CW. 

"A White House Christmas: First Families Remember" . . . 9:00 to 10:00 P.M. on NBC.  Michelle Obama and former First Ladies Hillary Clinton, Rosalynn Carter, Barbara and Laura Bush share memories of Christmas in the White House.  

Saturday:

"Prep & Landing: Naughty vs. Nice" . . . 8:00 to 8:30 P.M. on ABC.

"A Chipmunk Christmas" . . . 8:30 to 9:00 P.M. on ABC.  

"Mister Magoo's Christmas Carol" . . . 8:00 to 9:00 P.M. on NBC.  This animated version of "A Christmas Carol" stars the nearsighted Mr. Magoo as Ebenezer Scrooge.

On Christmas Eve:

"It's a Wonderful Life" . . . 8:00 to 11:00 P.M. on NBC.

"Prep & Landing" at 8:00 to 8:30 P.M. . . . which is followed by  "Shrek the Halls"from 8:30 to 9:00 P.M. on ABC.

"Christmas Is Here Again" . . . 8:00 to 9:30 P.M. on the CW.  This animated tale of an orphan out to find Santa's missing sack of toys.  It's voiced by Brad Garrett, Norm MacDonald, Ed Asner,Jay Leno and Kathy Bates.

"Second Star to the Left" . . . 9:30 to 10:00 P.M. on the CW.  An animated story of a rabbit, a guinea pig and a hamster who team up to help Santa find misplaced presents.  The rabbit is voiced by Hugh Laurie.

"Christmas with the Mormon Tabernacle Choir" . . . 9:00 to 10:00 P.M. on PBS. Jane Seymour and baritone Nathan Gunn perform with the choir.  (REPEAT)

 On Christmas Day:

"Disney Parks Christmas Day Parade" . . . 10:00 A.M. on ABC.  Lady Antebellum,Backstreet Boys, Colbie Caillat, Brad Paisley and Phillip Phillips perform.  Nick Cannon, Maria Menounos and Mario Lopez are your hosts.

Both the animated and live action versions of "Dr. Seuss' How the Grinch Stole Christmas" are on ABC.  Boris Karloff's animated "Grinch" airs from 8:00 to 8:30 P.M. and Jim Carrey'slive-action version is from 8:30 to 11:00 P.M.