Rest easy, Nurse Jackie and United States Of Tarafans. After big audiences tuned in for their season openers this week, Showtime promptly both shows. On the other hand, if you loved The CW's Virgin Air infomercial reality show Fly Girls, my suggestion is to savor every moment while it last. Its Wednesday-night debut drew a bare 1.2 million viewers. Worse yet, from a network ratings analyst's point of view, it lost more than 60 percent of the audience it inherited from America's Top Model. A crash-landing seems inevitable.