I think womens roles in film are a lot better than 10,20,30+ years ago. They are coming into a world of their own-even portraying the lead e.g/ Tomb Raider. I cannot bare to see women play the 'damsel in distress' type roles which often means missing out on some apparently good 'black and white' films. I think it is partly from being brought up in world pro-women, which is very different from back then, when women roles were strictly domestic.
I suppose that is the main difference, being that film mirrors reality, so as cultural values change they are reflected in modern films, especially western made ones.
Women have things to say, their characters are no longer two dimentional and there's no segregation [by this im meaning women can be portrayed in more than one role and are no longer sterotyped as being mothers and wives. To see this all you need look at is Angelina Jolie's or Julia Roberts careers and their roles.
Sure Katherine Hepburn was a great actress in her hey day, but there wasn't many roles for her. Could you imagine the roles she'd have now????