Only a few more shopping days before Christmas, but New York is already decked out like Tinseltown thanks to Tom Cruise, Nicole Kidman, and Whitney Houston. Far and away Hollywood’s most fab couple, Cruise and Kidman took Manhattan Dec. 6 and 7 with back-to-back premieres for his Jerry Maguire and her The Portrait of a Lady. The stars had all the right moves, but the Maguire soiree, held aboard the Celebrity Cruiseship (get it?), did not. ”I’m ready to get the hell out of this boat,” said Maguire costar Cuba Gooding Jr. ”I’m from L.A. When I feel movement under my feet, I run under a doorway.” Saturday was Lady night at New York’s Racquet and Tennis Club. There a Cruise-less Kidman (Tom had to return to the set of Eyes Wide Shut) played hostess to her starstruck family. ”I told them this is not what it’s usually like,” said the actress. ”This is suspending reality.” And speaking of the unreal, the only thing to eclipse Houston’s performance at the Dec. 9 Preacher’s Wife premiere at Roseland was the joy and goodwill generated by putting the soundtrack in the goody bag. Now that’s a stocking stuffer.