"It's one of those parties that you have to come to," Ciara, in head-to-toe Givenchy, told PEOPLE on her way in. "I'm excited to see everybody! It's cool to see people that you know, people that you don't know. It's always great to see Clive, and I'm just looking forward to having a great time."
Fergie, in a Zuhair Murad party dress, breezed down the red carpet in a hurry, stopping only to have a happy chat with Nick Jonas. But the singer had a good reason to rush: The Black Eyed Peas opened the show with Slash singing the classic Guns n' Rose's tune "Sweet Child O' Mine."
Newly engaged couple Katy Perry and Russell Brand sat front-and-center with pals Rihanna and Ne-Yo. On his way in the British comedian told PEOPLE his idea of a dream wedding. "I would like to have a Victorian wedding with a bunch of chimney sweeps and ravens and people on Penny Farthings coming along," he joked.
Later, Rihanna caught up with old flame Drake just as Harry Connick Jr. went on and got everyone clapping along to his amazing piano playing.
Taylor Swift, who is up for eight awards at Sunday's telecast, blew Clive Davis a kiss after he introduced her to the crowd. "It just hasn't even sunk in yet!" she said of her multiple nominations. But the country sensation is feeling optimistic, she told PEOPLE, thanks to her lucky number thirteen. "When I see it, it means that good things are going to happen, and I've seen it more times than I can even verbalize," she explained. "Every time I look at a clock, it's something-thirteen; the Grammys are happening on the 31st, which is 13 backwards; my producer was just given his ticket for the show, and he is sitting in seat 13. It just freaks me out!"
Kevin Mazur / Wireimage
Smokey Robinson gave PEOPLE a hint at what's to come Sunday, when he, along with Celine Dion, Jennifer Hudson, Usher and Carrie Underwood, pay tribute to the late King of Pop. "It's beautiful," he said of the performance they rehearsed earlier in the day. "We're having a great time and we are all paying tribute to Michael Jackson and the earth that we live on."
Jay-Z arrived after the event was in full swing (he'd been having a drink with producer and Interscope head Jimmy Iovine at a bar downstairs in the hotel) and gave Quincy Jones a warm hug on his way to his seat, while newcomer Ke$ha performed her hit "Tik Tok" on stage.
After Clive's bash, the A-list crowd made their way over to Iovine's house for a post-dinner party, where Mary J. Blige, Beyoncé, Sheryl Crow, Jay-Z, Diddy, Willi.am, Gwen Stefani, Akon, Maxwell, L.A. Reid, Keri Hilson, Drake and more all carried on into the night.
Reporting by Jessica Herndon and Reagan Alexander
Watch the 52nd Annual Grammy Awards on Jan. 31 at 8 p.m. ET/PT, live on CBS – and catch up on all the news and style from the show on PEOPLE.com!