"She didn't eat much. She drank double vodka cranberries. When they got up, Jessica was rubbing his back. You could definitely tell they were on a date."

Meanwhile a source for MSN spotted the couple "blissed out with each other" last weekend at the Four Seasons. The spy says, "They were eating off each other's plates. John rubbed her back [and] Jessica had her hand on his thigh as they leaned into each other and laughed."

Neither Jessica nor John are ready to fess up to more than a casual interest in one another. A source close to Jess told Us, "She's taking her time with it," while another Simpson camp insider told People magazine, that Jessica and John are "enjoying each other's company and seeing how things go. There's no title to their relationship."

One of Mayer's friends told Us, "It's a flirtation. I wouldn't call it full-on dating, but there is a fondness. He doesn't like the attention, but he likes her. He wants to avoid the public scrutiny of last time."