Brink is focused very much on the rpg aspect and as said before though female char would be refreshing they are not essential, you wont see yourself during gameplay (the reason most are buying the game!), female chars would essentially double the workload of an admittedly small team of animators and 3d modlers. And a DLC that contained the same kind of customization already in game but for females would break the game because it would cost 30 - 40 american dollars and would not be seen as essential and thus would split the community in those who bought the update and those who did not.
Brink is to close to release, if it is not pushed back, to basically make customization again as all clothes, features, tattos, statures, action animations, voices, and single player would need to be remade.
And Heavy women would look VERY strange if their size was comparable to Heavy males.
Primarily men play games and since video game companies need to make games fast and appeal to a large audience they had to comprimise.
Fallout is the only game I wouldnt play of the above due to its TPS nature. GoW scenery and enimies are epic enough that I never look at my char.