Since no one has jumped into the discussion on whether or not a woman may lead a Bible study in which both men and women are present I looked a bit on the question and answer section on wels.net.
It seems that the answers are vaguely clear in their position that it would be permissible. Here is a snippet:
The Scriptures clearly do not forbid women from engaging in all manner and types of teaching. The Scriptures clearly do not forbid women from engaging in all manner and types of teaching Scripture. Finally, the Scriptures clearly do not forbid women from teaching Scripture to men in every kind of circumstance and fashion. Colossians 3:16 assumes that the people of God will "teach and admonish one another.
So from what I can perceive the
Yet in returning to the upcoming Changers conference link you will see that this conference is encouraging this shift as there are several training session for women leaders.