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Jennifer Aniston Flaunts New BF While Cameron and A-Rod Get Caught "Holding Hands"

We've been waiting to say this for a long time, but...Jennifer Aniston has a boyfriend!
/ Source: E!online

We've been waiting to say this for a long time, but...Jennifer Aniston has a boyfriend!

And thank gawd his name isn't John Mayer.

The actress and her new man, actor Justin Theroux, made their public debut Sunday night at the MTV Movie Awards afterparty at Soho House in West Hollywood alongside a very much together Cameron Diaz and A-Rod.

So who had the bigger flirtfest?

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While a Sohogoer tells us Camrod were seated next to each other--talking and "holding hands" at a front table before leaving together fairly early--Jen and Justin arrived later in the evening and happily mingled with partygoers all night.

"Jen and Justin seem totally into each other and comfortable around one another," the party pal tells us of the Wanderlust costars. "Jen was going around and introducing him to people, and while they would sometimes go have separate conversations, they always wound up back by each other's sides holding hands."

Just like Cam and A-Rod!

"They are definitely dating for real," adds another source, who also saw Justin gently kiss Jen's forehead at one point in the night.

Aw, we're happy for Jen--let's just hope her new dude is 100 percent single!

The very recently not single Nikki Reed was also at the bash, chatting with fianc Paul MacDonald and friends.

"She seems so happy and definitely has that in-love glow," says our eyewitness.

And much to Team Truth's disappointment, our funnyman crush Andy Samberg is apparently very taken, as he didn't leave his hip harpist girlfriend, Joanna Newsom, at all night.

Let's just hope Andy isn't taking tips from pal Justin Timberlake on what to get his ladylove for the holidays.

--Additional reporting by Cristina Gibson

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