And Google has put up an interactive map (http://google.org/crisismap/2012-sandy ) that tracks Hurricane Sandy's progress and offers information on storm surges, forecasts and where to find emergency shelters.
The American Red Cross has an app called Hurricane that helps users update friends and family by simultaneously sending out messages on Facebook, Twitter, text and email. The app also offers locations of open Red Cross shelters, emergency plan checklists and location-based weather alerts.
"Social media has become the fastest method of disseminating information to a wide number of people," said Zeus Kerravala, an analyst with ZK Research. "For many people, it has become the de facto standard way communicating."
Kerravala, however, noted that people need to be aware that there could be a generational disconnect. Grandpa and your great aunt may not be going online as much to get your "I'm safe" message.
"Most of the senior generation won't be using it so it can't be the only form of notification," he added. "But I think there's a large percentage of the world that looks to Facebook and Twitter first. It's fast, easy and can be accessed from anywhere on almost any device."
Sharon Gaudin covers the Internet and Web 2.0, emerging technologies, and desktop and laptop chips for Computerworld. Follow Sharon on Twitter at @sgaudin, on Google+ or subscribe to Sharon's RSS feed. Her email address is email@example.com.
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