Aloha Aguilera

TMZ cameras spotted the couple in New York last night, all decked out for a luau -- Christina looking slightly tacky, though still hot in a polka-dot bathing suit, with Jordan island-ready in a Hawaiian print shirt and grass skirt.

It was date night for Kelly Osbourne, who stopped to take a few pictures with fans after dining at Mercer with an unknown, scruffy and long-haired male.

Looking far more dapper than Kelly's date was Diddy, who showed up to Marquee in a tux, after the annual awards of the Council of Fashion Designers of America. Aubrey O'Day, Diddy's Danity Kane warbler, hit up the after-party as well, showing a little PDA with NY socialite Tinsley Mortimer.

Also out: The magical stunter, David Blaine, who worked his magic to get into the club, "Asia" -- winner of the Pussycat Doll reality show, and rapper Chamillionaire.