Cell phones were virtually useless for the first few hours of 9/11 and the system was overloaded again during the east coast earthquake two weeks ago.

Texts often go through when cell calls won't.

Facebook turned out to be a very good resource for finding out the earthquake's effects around the region as it provided a lot of input in one place -- personal experiences and re-posts of news media reports. Facebook is also an efficient way of letting people know you're okay.

Facebook was also useful during Hurricane Irene. Friends and I used it to receive information and to lobby for attention from the power company after days of being without power.

Twitter could have provided a similar service as far as receiving and disseminating information, but I don't use my Twitter account much.

I'd be dealing with a lot more phone calls if not for Facebook and Twitter.

You should carefully consider the privacy controls available (or not), how wide you want your Facebook or Twitter circles to be and what kind of information you are comfortable with sharing with those groups.

Ever mindful that it could be discovered in a background check later on....