Kathryn Bigelow is the first woman to win an Oscar for best director, but is she a Thatcherite anomaly, or is Hollywood really changing?After every Oscar ceremony, observers traditionally attempt to distil a zeitgeisty trend from the proceedings, and the one available here would appear to be obvious. Yesterday, on International Women's Day in fact, we woke up to hear that Kathryn Bigelow had become the first woman to win the best director award in the Oscars' 82-year history.Women have, of course, been extravagantly admired as prizewinning actors at the Oscars and always been expected to provide the glamorous media faces of the Academy Award ceremony, the red-carpet icons and fashion queens. But never before has a woman actually been ...