I count December as Christmas time - right up until new years, but I went into the supermarket yesterday (boxing day) and they had taken down ALL of their Christmas stock and decorations!
For me, Christmas is about more than just Christmas day... There's loads of food left, the children are still buzzing with the magic of Christmas, memories of quality family time are fresh in our minds, we have loads of new toys to play with... Boxing day is definately still Christmas to me, as we have always gone round my Nan's the day after Chistmas for as long as I can remember. There's cold left overs, snack foods, Christmas crackers and a few more presents to unwrap and all in the company of our lovely big family :-)
The spirit of Christmas is still very much alive for me and my family. While the fire may be dwindling, the embers will still be hot for a while :-)