I read somewhere that the original Thanksgiving holiday for Catholics fell on St. Martin's Day (roast goose was the bird of choice) on November 11 and the protestants celebrated thanksgiving on a different day on purpose in order to take away the Catholicity of it (new world, new holidays - let's just remake the whole thing!)  I don't know how true this is, but I rather think it would be good to celebrate thanksgiving on Martinsmass day instead - although one of course would run the risk of being accused of not being patriotic or some such thing - and also no employers give Nov 11 off...