It really depends on the situation. If it's something like battle/combat, then those who are unable to defend themselves should be given priority of escape (provided all other things are equal). If it's something like the Titanic, with the exception of putting children on the life boats first (with at least one parent so that a) there are adults there to try and keep them alive, and b) that the children don't end up starving in the streets anyway), I think it is a rather inverted priority system. The people who push and shove their way onto the boats are the ones who value their lives at the expense of others, whereas the ones trying to help others onto the lifeboats are the ones with a sense of compassion, and are perhaps more valuable than those they help (possibly because they are acting as 'leaders', or because they represent the qualities of human interaction most conducive to mutual benefits).
So I don't believe in women and children first. I do believe in children first (from the perspective of a society/parent, we are responsible for them (as the continuation of our species, for example), and from the perspective of someone who doesn't feel that way, a child has more to lose than an adult, simply because they still have so much left to experience). Then the next priority is to determine if those who remain behind have a chance of survival (if they do, then the children's parents with the least chance of survival should be seen to next), as it makes sense for those most likely to survive to remain behind as a way of maximising the number of people likely to survive the ordeal, as well as providing the escaping children with a greater chance for a good life (by having at least one parent go with them).
