PHOTOS: How Kim, Diddy, J Lo, Luda, Rihanna, Holly looked New Year’s

Just a reminder: Stars get paid to “host” at nightclubs. And clubs forked over the cash and prizes for New Year’s Eve hosts. So ...

Kim Kardashian went to Tao with brother Rob, plus Brittny Gastineau, Hype Williams and other friends. Courtesy photos by Denise Truscello/Wire Image.

Now look, here’s Jennifer Lopez with hubby Marc Anthony at the “Love”show. How do they stay so thin? Courtesy photo by Denise Truscello/Wire Image.

And here’s J Lo’s ex, Diddy. Diddy did LAX at Luxor with Fabolous and Dallas Austin, plus an entourage of 30. Also at LAX: NBA's Tracy McGrady and Tayshaun Prince, plus Sherri Shepherd. Courtesy photos by Michael Tran/Wire Image.

This is what Holly Madison’s boyfriend looks like. He’s All Time Low guitarist Jack Barakat. They hung at Lavo restaurant with friend Angel Porrino. Courtesy photos by Al Powers.

And here's Holly, courtesy photo by Denise Truscello.

Rihanna in red counted down at club Pure. She brought 10 friends, family and security, and obviously ex-boyfriend Matt Kemp of the Dodgers wasn't there. Courtesy photo by David Becker/Wire Image.

At Hard Rock, Ludacris was at Vanity with friends and family, and performed seven songs: "All I Do is Win," "Stand Up," "Yeah!", "Glamorous," "Lick You From Your Head to Your Toes," "How Low" and "Move Bitch." Also there: Jason Giambi and wife. Courtesy photos by Hew Burney.

Ellen Pompeo dined with Samantha Ronson, Pompeo's daughter, and a male friend. Courtesy photo, Serendipity 3 restaurant at Caesars.

Dennis Quaid and wife Kimberly went to Nobo then Skybar, at Hard Rock, where they ran into Miss Nevada Sarah Chapman. Julia Jones of "Twilight" is staying at Hard Rock. Eating at Nobo last night: Chad Kroeger of Nickelback. And Pete Wentz at at Johnny Smalls without wife Ashlee Simpson. Courtesy photo Hard Rock.