The actress broke up with Justin Timberlake last January, after four years together. She seems very cozy with Mayer, who was dating Jessica Simpson. Mayer and Diaz were seen together in New York last Tuesday.
A source explained, "Cameron and John were strolling along the street hand-in-hand. They were nuzzling each other and looked besotted."
The couple went to Indochine Restaurant on Lafayette Street, to share an intimate meal. "They were very playful and cosy. They drank cocktails and lingered over dessert."
Diaz is in New York for the filming of the movie What Happens in Vegas.