Good move the by the Canadian Supreme Court. All making prostitution illegal does is hurt young girls trying to make a living by giving pimps and other violent men control over them. At the end of the day, women don't become prostitutes because they want to, they became so because they have no other choice. Better to protect them, allow for a more safe environment to make a living.
At the end of the day we're all adults. Adults should have the right to pay and receive money for sexual favors. We already do it for free. Why not allow those who need the money to have some food on the table as well.
Moral legislation never works. At the end of the day there will always be men looking for sex from prostitutes and there will always be women who have no other choice but to sell their bodies. People don't do it because they want to. People do it because they have no other choice. I've yet to hear a good argument for making prostitution illegal. Make it legal but controlled and you have a better world than you have now when you leave it for the underworld.