FOR MONTHS CARSON HAS BEEN SAYING, "What do I care? I'm out of here in May." Well, his devil-may-care attitude is getting more pronounced—and seeming less like a joke each week. Just before going to commercial after showing a bleep-filled clip of Mercedes Ruehl in The Fisher King, Johnny turned to the camera and announced, "And, by the way, the mystery words were *$%# and #@*&." The expletives were, of course, deleted again, but it didn't take a lip-reader to see what Carson was saying. Those NBC censors better keep their fingers on the bleepers. Johnny is going out with a bang.