It's very significant for U.S. citizens in Canada, because there are two parts of FATCA. The first is the part that deals with the banks, and the second part, which nobody ever talks about, has enhanced and very stringent penalty-laden reporting requirements for U.S. citizens abroad requiring them to disclose an unbelievable amount about their lives and their financial assets. Certainly that part of it would fall as well.
On May 14th, 2014. See this statement in context.