This year (2004) the Feast of the Holy Family will be observed on December 26. That does mean that the vigil will fall on December 25. I am not aware of a mandate that Masses on December 25 must be Christmas observance Masses; but, as the Feast of the Holy Family is not a holy day of obligation while Christmas is, individual churches may well decide to forego having a vigil Mass for the feast.
I suggest calling your local diocese to find out if there are any diocesan directives on the celebration of the feast this year.
