Since it relies on the existance of a working broadband connection, it isn't going be that resiliant in a major disaster...but then perhaps not much will be (maybe a standard, analogue phone line would be more resiliant). Then you'll be glad you got an amateur extra license so you can geek out and CQ CQ.
Thinking of the last "event", there was the last earthquake here in Seattle. As I recall, the cellphone networks were effected as everyone tried to call their mom at the same time, not because the network actually went down. The land lines do have an advantage in this respect, because they are more resistant to overloading.