Indeed, it doesn't seem to think that the fairly large cities of Vancouver, Calgary, Edmonton, Regina, Winnipeg, and Thunder Bay have a population of approximately zero. Anywhere in northern Montana has the "beam" shoot all the way over to Maine before reaching 100K, which isn't quite right since it passes through a couple medium Canadian cities and dozens of prairie towns.

I think this tool would be much more interesting in the western US if they had incorporated Canadian census data as well.