updated 06/17/2010 AT 4:00 PM ET
•originally published 06/18/2010 AT 6:00 AM ET
John Mayer celebrated friend DJ Soul’s birthday at club CV, where the singer requested some obscure songs. Mayer was drinking beer and celebrating – then Tweeted that he would be performing a spur-of-the-moment gig at New York’s Village Underground at 3 a.m. Two hours later, the singer took the performance to the street, where he sang and danced a bit more.
Rachel McAdams, dining alfresco at Bar Pitti in New York, with three older men and a female friend. The actress drank red wine and nibbled on a salad and bread, looking relaxed and letting her friends talk. After dinner, the group moved to a nearby bench, where they people-watched and chatted until 11:30 p.m.
New couple alert? Paris Hilton, supporting rumored new beau Cy Waits at the opening of the lounge downstairs at Drai’s Hollywood. The two walked in hand-in-hand and were all over each other, sharing hugs and kisses in front of clubgoers. Hilton checked out the scene, then went back to her PDA with Waits before heading upstairs to hang out.
Nicole "Snooki" Polizzi, playing bartender at Prime KO on New York’s Upper West Side. The Jersey Shore star happily served drinks, then enjoyed a meal – consisting of sashimi tacos, tuna pizzas, sliders and more – with castmate Vinny Guadagnino.
Adam Lambert, showing off his new hairdo during a meal out at Hub 51 in Chicago. The rocker lunched with 14 people at the restaurant’s private upper deck, and enjoyed a tuna and truffled egg sandwich as well as an iced tea.
By DAVID CAPLAN, PAUL CHI, JENNIFER GARCIA and LESLEY MESSER