Paparazzi Photo

Leonardo DiCaprio is clearly enjoying his single status and partied it up on a yacht with a bunch of hot bikini babes in Australia over the holiday weekend.

Along with all the sexy chicks -- some of whom were topless -- the 38-year-old "Django Unchained" star also hung out with his wingmen Jonah Hill and Lukas Haas.

Up until around two months ago, DiCaprio was dating Victoria's Secret supermodel Erin Heatherton.

Forget Lamaze classes -- Kim Kardashian's fetus is already getting its daily workout ... at the gym.

Kim -- who's roughly 3 months pregnant with Kanye West's baby -- took her barely-visible baby bump out for a cardio sesh this morning in L.A.

From the looks of it ... Kim's taking a page out of Jessica Simpson's maternity wardrobe playbook -- lots and lots of black clothing.

But we'll give her credit for the spandex. Then again ... she's only 12 weeks into this.

Facebook founder Mark Zuckerberg is white hot -- exposing his burly man chest while vacationing in Maui.

Zuck wasn't shy about sharing his topless physique while taking his wife Priscilla Chan out for a private surf lesson.

See, there is something $14 billion can't buy.

Chelsea Clinton was visibly upset as she left the NYC hospital where Secretary of State Hillary Clinton is being treated for a blood clot in her head -- although doctors now say things are looking up for Madam Secretary.

Chelsea was photographed outside New York Presbyterian Hospital Monday after visiting her mom ... who's been there since Sunday when doctors discovered the blood clot during an MRI.

The photos tell the story -- it was a rough year for Lindsay Lohan.

These pics of Lindsay were snapped as she returned to her London hotel just before the stroke of midnight.

Lohan looked disheveled and a little bloated after celebrating the end of a year that included --

-- a car crash
-- 3 fresh criminal charges for lying to cops
-- getting her probation in the jewelry heist case revoked
-- arrested in NYC for assault
-- arrested in NYC for hit and run
-- calling cops after epic fight in NYC with Dina
-- huge tax problems
-- Liz and Dick
-- Liz and Dick
--Liz and Dick

Kim Kardashian and Kanye West's pregnancy was far from an immaculate conception -- but it did go down in the shadow of the Vatican ... TMZ has learned.

Our Kim K. sources -- which are immaculate -- tell us the deed was done back in October ... during Kim and Kanye's romantic trip to Italy to celebrate Kim's 32nd birthday.

The couple was photographed all over Rome as they toured the Colosseum, the Sistine Chapel, and, of course ... the Pope's pad.

We're told Kim is about 12 weeks along ... so the math adds up.

One clue about how important that Italy trip is to Kim -- her blog lists it as #2 on her top 10 best moments of the year.

Kanye West and Kim Kardashian were all over each other -- like a couple o' teenagers -- when they touched down in LA this morning ... just hours after announcing they've got one in the oven.

KK & KW were arm in arm -- a few paces behind proud momager Kris Jenner -- as they strolled through LAX ... but it won't be long before the couple and their little (very little) one are back in the air.

As TMZ first reported ... Kim's going through with her scheduled NYE appearance tonight at 1 Oak Nightclub in Las Vegas.

Kim Kardashian wasn't going out of her way to squash all those pregnancy rumors -- in fact, in hindsight ... she damn near handed the world her ultrasound.

Just last week Kim and daddy-to-be Kanye West were spotted arm in arm leaving her OB-GYN.

DUH!!

We all know the only reason a dude accompanies his lady to that doctor is if she's having your baby.

As TMZ first reported, Kim and Kanye's original plan was to keep the baby hush-hush until she started showing and people started asking questions.

Olympic legend Michael Phelps has broken up with girlfriend Megan Rossee ... TMZ has learned.

Look at the photo above, then read that sentence again.

According to our sources, Phelps felt the relationship wasn't going anywhere, so he decided to end it so he could pursue other options.

And apparently in the world of Michael Phelps, those options are somehow better than this.

Cameras follow Lindsay Lohan everywhere she goes, but she's not about to live with them ... telling friends she has no interest in doing "Celebrity Big Brother."

With LiLo arriving in London yesterday (see above), the rumor mill spun into overdrive ... saying Lindsay was in town to film the super-popular British show.

But according to our sources, the idea is "completely untrue" and total "nonsense." As one source pointed out ... how could she lock herself in a home for a few months when she has a court date next month?

Doing her best Dennis the Menace impression, Kristen Stewart hopped out of a truck in L.A. armed and not-so-dangerous ... with a slingshot in her back pocket.

We don't know what the 22-year-old was taking aim at yesterday, but as long as it's not married directors ... everything should be fine.

An 18-year-old looking after a 3-year-old is pretty ordinary, but when that 18-year-old is Justin Bieber and the kid you're watching is the son of L.A. Clippers star Chris Paul ... AND you do it courtside at Staples Center ... it's just awesome.

Bieber had a front row seat last night as little Chris Paul II watched his daddy and the Clips dismantle the Boston Celtics, 106-77 -- which propels the team's winning streak to 15.

With her guardianship situation settled for the moment, Ariel Winter spent yesterday acting like an actual 14-year-old girl by going go-karting in Burbank.

Winter's sister, Shanelle Gray, cemented her role as temporary legal guardian earlier this month, with her lawyer and dad now in control of her finances.

But soft! What light through yonder window breaks? It's Jennifer Aniston, who continued her ridiculously hot Mexico vacation yesterday ... looking pensive in a sexy bikini and an exotic red sarong (the thing wrapped around her waist).

As we reported, Jennifer and her tatted-up fiance Justin Theroux have been kicking it in Cabo San Lucas over Christmas, and things just keep heating up.

Still unclear if Jennifer's pregnant -- but if you're wondering what it's like to get held up in Mexico ... just ask her boobs.

Heidi Klum performed a supermodel magic trick Wednesday ... riding bitch with an extremely large helmet and then removing it ... only to reveal a perfectly coiffed head of hair.

Heidi was riding with her bodyguard-BF Martin Kristen in Venice, CA when she showed off her hat trick.

They've taken a serious step in their relationship, wearing similar get-ups, including hipster sunglasses.

Jessica Simpson and Eric Johnson are going to extremes to hide something -- like every inch of their bodies during their family vaca in Hawaii.

We've already seen Jessica covering up on the beach since announcing her pregnancy ... but during a Christmas Eve stroll on the beach even Eric was cloaked from head-to-toe while carrying baby Maxwell.

Far as we know ... Eric doesn't have a deal to drop lbs on Weight Watchers.

The only Simpson not in undercover mode these days is Ashlee Simpson ... who proudly showed off her bikini bum.