If you are reading this post on December 21, 2009 at 9:47 AM, you are experiencing the winter solstice. Wikipedia defines the winter solstice here.
The actual solstice only lasts an instant, but on this day there is more darkness than light.
From December 22, 2009, until the Autumnal Equinox, the amount of light in each day will increase in small increments. We are, literally, crossing over from the dark and into the light.
Isn't that wonderful news? Just when it is the darkest, the light is seen on the horizon.
Merry Christmas to all!