While Christmas music is supposed to be timeless and long-lasting, evidently there are several distinct eras of Christmas music. Using comic book eras, this is how I'd break them:

Platinum age: Antiquity to 18th Century (O Tannebum/Christmas Tree, Greensleeves, The First Noel, Messiah, God Rest Ye Merry Gentlemen, Angels We Have Heard on High, Joy To The World, etc.). The most traditional, mostly used in places of worship these days.

Golden Age: 19th-early 20th Century (Jingle Bells, O Little Town of Bethlehem, Deck the Halls, Silent Night, The Twelve Days of Christmas, We Three Kings, Jolly Old Saint Nicholas, etc.) Timless songs enjoyed equally in church and in public. The first songs about Santa Claus appear. Even still, this era has some long obscure carols, such as "The Voice of the Christ Child" and "Christmas Once is Christmas Still'.

Silver Age: mid-1930s-early 1960s (White Christmas, The Christmas Song, Up On The Housetop, Holly Jolly Christmas, Silver Bells, Have Yourself a Merry Little Christmas, Winter Wonderland, Rockin' Around The Christmas Tree, Rudolph The Red-Nosed Reindeer, Frosty The Snowman) Basically the heyday of classic secular carols, indicitive of the rise of the capitalist society, yet consistantly has a high rate of classics still enjoyed to this day, despite some now obscure songs in the mix. But there were still some religious-friendly songs like Mary's Boy Child.

Bronze Age: mid-1960s-mid 1980s (Feliz Navidad, This Christmas, Merry Christmas Darling, Step into Christmas, Do They Know It's Christmas?, Last Christmas) A mixed bag with some newer classics that have survived the test of time along with some now obscure ones (CB Santa, Ring Out, Solstice Bells, and much more). Much more indictitive of it's era and tends to be more specialized (Spanish, R&B, Synthpop). Quite a dropoff in selection from the Silver Age, as rock music was at its peak and focused more on getting the next big hit rather than the Christmas classic.  

Copper/Modern Age: Late 1980s-present. Mostly covers of standards with only the occassional classic (All I Want For Christmas Is You, Trans-Siberian Orchestra's hits) sneaking in due to a saturation of classics. The originals (Hey Santa) get little or no airplay due to poor reception for most new material. Bottom line: More choices than the bronze age, but of lower quality and originality.

The copper age of Christmas Music?  I think you need to stop smoking that crack pipe

The copper age of Christmas Music?  I think you need to stop smoking that crack pipe


I'm actually with him on this one, although I think he got the decades wrong.  It doesn't matter when the carol was written, it matters when the "canonical" version of it was recorded.

Because there's an xkcd for everything:

http://imgs.xkcd.com/comics/tradition.png

"An 'American Tradition' is anything that happened to a baby boomer twice."

Disclaimer: I listen to John Valby at Christmas, so my idea of "canonical" when it comes the classics is somewhat different, and skewed towards the 80s/90s/00s, and the lyrics are unprintable in a safe-for-work forum :)