In fact, why care about the ancient Church Calendar at all?
Rob Bell serves up an engaging introduction to this topic; igniting my own interest in the church calendar which has been kindled over the last couple years.
I ordered Eternal Seasons: A Spiritual Journey Through the Church's Year by Henri Nouwen to help find my place in the rhythm of the new Church Year.
The Liturgical Year: The Spiraling Adventure of the Spiritual Life - The Ancient Practices Series and Living the Christian Year: Time to Inhabit the Story of God look good too. Should make for some good reading over the next few Church years.