With little fanfare, the Canadian government recently introduced legislation that breaks with conventional trademark law and would grant the Vancouver organizing committee rights to "winter" and a long list of other common words, among them: "gold," "silver," "medals," "sponsor," "games," "21st," "2010," as well as the name of the host city itself. The legislation would also give the committee special enforcement powers.
This is an attempt to prevent ambush marketers from hurting sponsors. Turns out though, that this is common practice: "Other countries, including Britain, have passed similar legislation. But in Canada the plan has met with criticism from those who dislike the notion of common words becoming private property, even temporarily."
I'm going to have to go with the disgruntled Canadians on this one.