02/03/2009 at 03:00 PM EST
, rocking out in the front row at Katy Perry
's Los Angeles concert at the Wiltern. Nearby, Josh Groban
scoped things out – and the two seemed especially into the opening act, The Daylights
. Then, it was time for Perry, who performed on a stage adorned with inflatable fruit.
It's a Grey's Anatomy
reunion! Former costars Kate Walsh
and Sara Ramirez
enjoyed dinner – and margaritas – with a large group at STK in West Hollywood. After, they headed to the adjoining lounge Coco de Ville for a night of drinking and dancing. "Kate was in a great mood and was having a blast with her friends," an onlooker says. "They couldn't stop talking about how excited they were to go out together."
, eating dinner with reported new beau Josh Lucas
at New York's Waverly Inn. The two were sharing macaroni and cheese, an onlooker says, though very few people in the restaurant seemed to notice the pair. While they ate together, McAdams stayed behind at the bar with a female friend, while Lucas left, putting on a baseball cap before heading out.
had family by her side while celebrating her 32nd birthday at RA Sushi in South Miami. The Colombian singer wore no makeup to the dinner party and "seemed really happy to be with her family," a source says.
He wasn't there for the coffee, but Jake Gyllenhaal
was deep in conversation with a mystery blonde at his favorite hangout, Caffe Luxxe on Montana Avenue in Santa Monica. Dressed down in a gray T-shirt and jeans, the actor appeared to be interviewing his companion, onlookers say. The two chatted for 30 minutes and left separately without ordering anything.
By JENNIFER GARCIA, LISA INGRASSIA, LINDA MARX and LIZ MCNEIL
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