Brief update: still no baby. Thanks again for all the interest and good wishes. Pip put in another fine performance on the fetal monitor this morning, so there's no sign of anything to worry about other than the date. (The fetal monitor tests the baby's movement and heart rate to make sure that the placenta is still intact and keeping the baby healthy. This is important because placentas are not made to last much more than nine months.)
I noticed yesterday that I had been assuming Carolyn and I both faced boatloads of people asking us whether baby has come yet when we leave the house separately. I finally thought about that for a minute and realized that nobody sees Carolyn and then asks that question. Duh.