This article from The Independent in 2006 http://www.independent.co.uk/environment/green-living/high-environmental-price-of-a-very-merry-christmas-429635.html shows just a few statistics about how much waste is created over Christmas. According to this article 40% of food bough of over Christmas is wasted it also states that out of the 6 million Christmas trees bought only 1.2 million of them are recycled. Another website also has some facts about waste over the latest Christmas period in 2009 http://www.recyclenow.com/christmas_09/festive_facts.html.
However unsustainable Christmas might be, it's a time of the year that everyone looks forward too and the fact it's unsustainable won't stop people celebrating it and to continue wasting as much as they want. I couldn't see Christmas ever being a sustainable event however there are more and more schemes being put in place to try and make it more sustainable. This government run website shows some of the schemes put in place to try and make Christmas a more sustainable event, http://www.recyclenow.com/christmas_09/christmas_cards.html.
Christmas will never be sustainable event because I think people don't care enough during the Christmas period as it's a time for giving and having a stress free good time. However I do think that once Christmas is over it's easy to recycle cards and trees and as a result attempt to make it more sustainable.