Thanks to Peggy, I learned that Fr. Z has a poll of readers asking whether they think head coverings for women should be obligatory at Mass. The problem with the poll is it operates under the assumption that it is not already obligatory. As the great Unknown Canon Lawyer X as already demonstrated, this requirement is still in effect; it was never abrogated. It is an immemorial custom with the force of law, nor did the promulgation of the new Code of Canon Law in 1983 affect it. I urge to read his article, if you have not done so already.
Fr. Z is aware of this argument, and though he is of the position that head coverings are a great tradition, and that they should be worn, he simply restated his position that they are no longer obligatory without addressing the substance of the argument by the Canon Lawyer above.
This requirement is not on the radar of most Catholic women, and most either never knew of it or else believe that the obligation was done away with. So, my point in all of this is not to assign guilt to anyone, but to use this little vehicle to spread the truth of the situation as much as I can.
So, vote away on the poll, but be aware that the list of choices is decidedly incomplete.