-- Last Updated: Dec-19-12 6:51 AM EST --
If you anticipate making longish open water crossings in cold water conditions and you have a solid roll, and/or self-rescue ability in your kayak, then a kayak would be safer.
Some of the larger lakes up in the Canadian Shield country can take more than a day to paddle around the perimeter of but can be crossed in an hour or less. Yet the water in those bigger lakes remains quite cold well into summer. A solo canoeist, or a solitary couple in a tandem, capsizing half a mile from shore might well not survive the swim.