The Christmas Alleluia

This is the text of the Alleluia verse for Christmas Day:

Alleluia. Dies sanctificatus illuxit nobis;
venite gentes et adorate Dominum,
quia hodie descendit lux magna super terram.
Alleluia.

Alleluia. A holy day has dawned for us;
come, nations, and worship the Lord,
for today a great light has descended over earth.
Alleluia.

And here's an interesting video of the "Alleluja di Natale - canto gregoriano nell'interpretazione di Giovanni Vianini direttore della Schola Gregoriana Mediolanensis - Basilica di San Marco Milano, Italia":



Here's the chant score from the Brazilian Benedictines (and their mp3 version):