For centuries, Christmas has been celebrated with many traditions that are not Christ centered. Christmas trees, Santa Clause, and so many other Christmas traditions are not really Christ focused. Things like angels and nativity scenes are a part of what the true Christmas is about.
Sure, Christ was not actually born on December 25th, but it is the day that we celebrate it. In the year 2011, this date falls on a Sunday, which has been our given Sabbath for about 2 millenniums. The sabbath is our day to put off our work, and things of the world, and focus on Christ. On a year that this holiday falls on the Sabbath, I like to cancel the traditionals that are not Christ centered, so I can expirence Christmas the way my maker intended me to. It gives a special feel to Christmas throughout the Christmas of that year as well as future years.