Lions and tigers and. . . Jasper Johns? Oh my! That may have been your first reaction too, when you saw the glammy 20-page Annie Leibovitz "Wizard of Oz" spread in last month's Vogue, in which famous artists play all the major roles, except Dorothy, who is represented by the super-long-necked British starlet Keira Knightley, outfitted in Balenciaga and the like.