Elizabeth Johnson in Truly Our Sister observes that Mary, in singing the Magnificat, becomes a member of that great list of women singers and preachers, first peppering the OT and making its final and greatest appearance in her song. Of course, the preaching of women continues in the NT as well, in Acts, those women gathered together with the disciples. For profound and stunning reflections on these texts in-depth, I commend Johnson's exegetical commentary in the center of her book, as well as the final synthesis chapter on the communion of saints. I also recommend that her entire work be savored, for it is worthy of close attention.
But here I post a simple observation. Structurally, if you look at Luke from a literary perspective, the Magnificat parallels in a chiastic fashion the announcement of the resurrection by the women. The proclamation of women book ends Luke, if you will. It opens with the wild prophetic proclamation of Mary on the Incarnation. It ends with the (presumed crazy until verified by sight by the male disciples) testimony of the women to the resurrection. The ordination of women may continue to be a sticky wicket from an ecumenical perspective (see Louis Smith's to my mind annoying essay in the most recent Lutheran Forum, for example), but from my reading of Luke, at least, women as preachers and prophets and speakers of the Word is a no brainer. Silence on Saturday, yes. But when the time comes to announce the Resurrected one, women are first in line.