03/11/2010 AT 06:00 AM EST
got the best seat in the house for opening night at L.A. nightspot Trousdale. The pop star, in a short blonde wig and black hat, played musical chairs once she got to her table, whispering in her friends' ears and moving around her booth. Gaga was in a pleasant mood, but got really excited and started dancing when the deejay played her hit "Paparazzi." Meanwhile, Hayden Panettiere
worked the room, chatting at friends' tables when she wasn't hitting the dance floor with a girlfriend.
, vintage shopping at the What Comes Around Goes Around boutique in L.A. with her puppy, Mate, and a girlfriend. Shoppers were especially attentive to her pooch, but Cyrus was focused on the clothes. She tried on various items, and left with some boyfriend jeans, cut-off denim shorts and vintage T-shirts.
was sampling his own 901 Silver Tequila
during a night out at Lavo in Las Vegas. The singer-actor also danced to tunes spun by DJ Crooked, and was spotted dining at Tao earlier with friends and business associates.
It's a Today
show reunion – but was it also a business meeting? Matt Lauer
and former co-anchor Katie Couric
, lunching at Le Caprice inside New York's Pierre Hotel along with Andrew Lack, CEO of Bloomberg LP.
, dining in an alcove at Rouge Tomate in New York with husband Michael Douglas
and two friends. The group stayed for two hours, chatting about the Oscars, among other things, and drinking red wine.
By JENNIFER GARCIA, MARK GRAY, MAUREEN HARRINGTON and LIZ MCNEILWednesday's Caught in the Act >