Cameron Diaz and John Mayer were "all over each other" in New York at the weekend.
The 'Shrek the Third' star and the singer - who were first seen together last week - were canoodling at the Bowery Hotel on Friday (08.17.07).
A witness told People magazine: "They were all over each other and super flirty. They sat on a couch in the back of the patio and were laughing and talking a lot."
When asked if the pair were dating, a source close to Mayer said: "Yes, it's definitely true."
The pair were first seen together having dinner at French-Vietnamese restaurant Indochine last Tuesday (08.14.07).
Diaz - who is in New York filming new romantic comedy 'What Happens in Vegas.' - split from her boyfriend of four years Justin Timberlake in January.
Mayer, 29, split from on/off girlfriend Jessica Simpson in June.
Last Thursday Diaz, 34, was also seen dining-out with co-star Ashton Kutcher and three other men at La Goulue.
Demi Moore was NOT in the house.
Last week John Mayer was spotted at a liquor store buying what appears to be two bottles of wine.
