I said "may" because those discussing the issue on the Microsoft included those who rebooted and were affected and others who rebooted without being affected.
What happens to Windows users if something happens to the existing WGA server installation that is more or less permanent? It could be anything, fire, earthquake or terrorist attack to name 3. What happens to the economy if that were to happen? Does Microsoft have multiple non local backup systems in place to start up immediately (in which case where were they in this instance?)? If they don't have such backups why the heck not? A single point of failure is not acceptable.