Thanks to Jan, over at a Church for Starving Artists, who asks: Is Blue the New Purple? for the season of Advent. You put a bee in my bonnet to see what I could find out about the shift in color for Advent. (As a PhD student in Liturgical Studies, these kinds of questions get my juices flowing!)
Jan mentions that she likes the color purple because it highlights Advent as a mini-Lent. This gets at the crux of the shift in color association. The shift from purple to blue occured largely in order to distinguish the themes of Advent from the themes of Lent, to make the seasons more distinct from one another. (In addition to being a brilliant marketing ploy, as Jan muses.) :)
But the very theme of penitance has been a sticky one in recent liturgical reformation movements. For instance, in the Eucharistic service for the United Methodist Church, the prayer of confession is moved away from the Table part of the service and up to the front of the worship service--in order dissociate the feeling that we have to "get ourselves right with God" before we can approach God. For those of us shaped even a little by the Lutheran tradition, this is a grace-filled move.
In addition, even the theme of penitance during Lent has been tempered in recent years by liturgical theologians. Lent as a season for the preparation of baptism (and re-affirmation of baptism) has been emphasized even more than penitance.
Blue for Advent, therefore, also serves to downplay the theme of penitence. It is intended to lift up the eschatological aspect of Advent (our longing for the reign of God to be fulfilled). The emphasis on eschatology is also meant to serve as a corrective, I believe, to a more historicist approach to the season which is often dominant in our churches. The historicist approach tends to make Advent a season of Make-Believe--when we make believe that the baby Jesus hasn't been born yet, a wink-wink, nudge-nudge approach to experiencing the story of our faith.
The apocolyptic texts of the lectionary enforce the eschatological emphasis, making it near impossible to cozy up to the notion of pretending we're waiting for the baby Jesus--rather, we find ourselves trembling with the mountains at the anticipation of the Day of the Lord.
This year, I've been able to re-connect a sense of penitence to that anticipation. Though it has not been a personal-sin penitence, but a corporate, systemic, liberation-theology sense of Sin that has informed my vision this year. I've heard Mark's demand to "Stay awake!" and John's call to repent more in these terms.
The change from purple to blue is a fascinating, contemporary opportunity to observe how liturgical change takes place. Clearly, some liturgical "experts" likely empassioned by the ecumenical and liturgical movements, thought it would be better if we used blue rather than purple for Advent. Little by little, churches on the local level began to pick up on this shift. (Memos were distributed in seminaries, perhaps.) :) Now we're seeing a real mixture of practices on the local level. Ultimately, I believe, this is where liturgical change either takes hold or doesn't. Ultimately, it ain't what the experts say they want, but what the people do.