[For those of you who won't be at midnight Mass yourselves, you may want to look into this option.]
The U.S. Catholic radio network Relevant Radio will be providing live transmission of the Christmas Midnight Mass, celebrated in the classical Roman liturgy, from St. Joseph’s Oratory, the Institute of Christ the King’s apostolate in Green Bay, Wisconsin.
To listen online: http://www.relevantradio.com/docs/index.asp?documentid=966
(Midnight Mass from Holy Trinity German Catholic Church, Boston)
(I'd also recommend trying to catch Midnight Mass from St. Peter's Basilica in Rome, which is usually available on most major network, but likely also to be watchable online on Vatican TV.)