I was just talking to a new nurse on our unit about the aftermath of Katrina (here in Baton Rouge).

I remember how many family members were desperately looking for each other and how many tearful reunions I watched. Facebook wouldn't have solved this but it would've been a very valuable tool for someone to put a post up "I'm here in Baton Rouge and I'm ok".

This creates of course a number of problems, (How do you get computer access in an emergency if you don't have an iphone, the "lost" individual being incapacitated and can't communicate with others, etc).

One never solves problems. One only trades off consequences.