This year marks the 50th year that the U. S. Post Office has been producing special stamps for the holiday season. I have a soft spot for the first Christmas stamp, the 4-cent Wreath and Candles. It is a simple red and green stamp with a wreath, two candles, and the words "Christmas 1962". I still come across unused stamps from this issue and happily affix them to my outgoing holiday cards.
You might think that the first stamp of something might be rare, but the demand for the stamp was so high that the Bureau of Engraving and Printing printed 350 million of them to start which was the most ever printed for a specialty stamp at the time. It wasn't enough. They went back to press and by the end of 1962, they had produced 1 billion of these wreathed beauties.
Every year since, the Postal Service has issued two holiday stamps; a "Holiday Contemporary" stamp (the Santa and Sleigh for this year) and the "Holiday Traditional" stamp (the Holy Family for this year). In 1996, the first Hanukkah stamp was produced, followed by a Kwanzaa stamp in 1997 and an Eid stamp in 2001. While there aren't any new designs this year, they are still selling the inventory of the designs from past years.
You can find a detailed listing of all the U.S. holiday stamps here. You can see all the holiday issues from around the world over on Stamp News. Lastly, for those of you who love Christmas stamps more than anything, there is a stamp club for you.