May 12, 2007 and July 7, 2007
Jamie McCarthy/WireImage.com and Dimitrios Kambouris/WireImage.com

Seven months after her breakup with Justin Timberlake, Cameron Diaz has found another singer to swoon over!

And she's showing him off. When the actress hit NYC eatery Indochine with John Mayer August 14 for an evening of flirting and sipping wine, they settled into a cozy both right in front.

"People did double takes," an eyewitness tells Us Weekly of the pair, who talked, smiled and giggled endlessly.

"It was cute, like they were just beginning dating."

Three days later, it was more of the same as the new couple got touchy while having drinks on the patio of NYC's Bowery Hotel.

Those close to the duo, who met through mutual pals and have known each other for a while, aren't surprised by the pair's PDA; in fact, they wonder what took so long.

"She has always said she was a fan of his music," a Diaz insider tells Us, "and he thinks she's beautiful and really smart."

And the pal adds, "They are both so funny and have a dark sense of humor. It is a natural fit."

But they're not exclusive yet: Mayer, 29 - who recently called it quits with Jessica Simpson - was spotted chatting up a bevy of beauties at NYC hot spot The Box on August 18.

A cautious Diaz, 35, is taking it slow.

"She likes everything about him so far," says the Diaz source. "He's wicked-smart, socially aware and into politics and the environment. But it's very new."

For more details on hot celebrity romances, check out the new issue of Us Weekly, on newsstands this week.

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