Justin Timberlake reunites with Cameron

Justin Timberlake and Cameron Diaz reunited Friday night at the Whiskey Bar in the Sunset Marquis Hotel in West Hollywood.

Timberlake had joined director Martin Scorsese and about eight other people at a table inside the hotel's exclusive bar. Then, at about 1 a.m., Diaz arrived.

"Cameron never joined their table," says the observer. "She just showed up and Justin got up and started talking to her. They were being very discreet. "They weren't kissing or holding hands or anything, but they were being very friendly," the observer adds.

Then walked out the front door together a half-hour later. Says the onlooker: "When I first saw this girl, I thought, 'That's not Scarlett Johansson or Jessica Biel.' Then it hit me – it was Cameron! She was low-key, her hair was dark and pulled back."

I wonder if they talked about Justin’s new song…