All Fios Services Down

How big a deal is this? I'm not familiar with Verizon as an ISP, like Comcast. Does Verizon have lots of Fios customers?

The other question is: how do all Fios services go down at once? Verizon used to be a baby bell roll-up. The Bell System was not centralized. Failure of one system or region absolutely had no effect in adjacent regions or systems.