From “That’s Canada…with a ‘u’!” by Robyn Matthew in West Coast Editor, February 2005:

Whether they like it or not, Canadian publishers are being forced to tailor the spelling of their books to an American audience, which is 10 times the size of Canada’s, simply to remain financially viable. “We are doing more American spelling because we are selling into the states,” admits Nancy Flight, editor at local Canadian publisher Greystone Books. And she adds, “some authors are really upset about it.”
The sacrificing of Canadian spelling has also saddened many Canadian editors, even though they understand the economic reasons behind the decision. “Americans,” states Liv Fredricksen, “typically like things to be placed within their own frame of reference, and they have the buying power to demand that the rest of the world comply.”

The newsletter containing the entire article should be posted soon on the EAC website,