When Robert Peyton joined the micro-blogging service Twitter during its earliest days in 2006, it was just a place to rave about New Orleans' finest eateries and keep in touch with friends.
But as the 39-year-old lawyer tried to keep tabs on Hurricane Gustav and the fellow New Orleanians whose lives were upended by the storm, the service turned into an invaluable source of information, he said.
Unlike blogging services that allow users to post comments only from their computers, Twitter lets posters "tweet" from cell phones, smart phones and computers. All tweets -- 140-character messages -- are sent to the user's Twitter page online, but others can sign up to receive them via their own cell phones, smartphones and computers.
When Peyton lost power in Baton Rouge, he could receive tweets from a New Orleans Twitter community that spanned the Southeastern states. In turn, from his own smartphone, Peyton sent messages to the nearly 100 people who had signed up to receive his updates.
Peyton acknowledges that the information distributed through Web sites, SMS messages, instant messages and other social networking sites is only as good as the person sending it. But as he rode out the storm in Baton Rouge, he said it was one of the only ways to get accurate local reports from New Orleans.
"The national broadcasts are just kind of silly and alarmist," he said. "It's nice to have something to balance that out."
Mark Folse, a project manager for a financial institution and another New Orleans blogger, agreed.
In the past few days, the self-proclaimed "weather geek" has funneled information he uncovered from reliable weather Web sites to his Twitter page. Twitterers with interests or expertise in other areas provided their own additions to the online conversation.
"It's been of tremendous value," he said. "People take on a role for themselves and then feed it into the larger group."
On his 12-hour trek to Memphis, Tenn., with his family, he received a constant stream of updates from other evacuees about the traffic, the weather and even a Labor Day Memphis music festival.
"Embeds" -- bloggers who stayed behind in New Orleans -- provided hyper-local information about various neighborhoods, he said.
Sheila Moragas, another local blogger who evacuated to a hotel near the Louisiana State University with her husband and toddler, said one of the "embeds" offered to check out her house when the storm passed and then Twitter about it for her.
"Twitter becomes your online neighborhood," she said.
CNN and other major networks reported ony on the places with the most action, she said. But because Twitter users live throughout the city, they could provide more local coverage.
Since Hurricane Katrina devastated the city in 2005, blogger Folse said, a core group of bloggers has been building a Twitter community that would be useful in emergency situations.
Maitri Venkat-Ramani, a 10-year blogger who was instrumental in building this network, said, "During Katrina, we were helpless, scattered to the winds and at the mercy of national news networks. We didn't have a lot of people on the ground and didn't have a lot of connection to each other.
"After Katrina, we [made] unified efforts to talk about recovery on blogs and form a comprehensive network of blogs ... that would really elevate the [most] important news pieces."
From her evacuation site in Birmingham, Ala., the 33-year-old geophysicist told ABCNews.com that as an early adopter of Twitter, she realized its effectiveness as an information-dissemination tool in emergencies. In one go, you can share any detail of your life with potentially thousands of people.
At the beginning, she said, some scoffed at mundane Twitter posts about what users ate for lunch or watched on television. But now, more than 300 bloggers comprise a loosely affiliated network and meet annually at a conference called Rising Tide to strengthen the alliance and discuss ways to rebuild the city.
Although not affiliated with Rising Tides, the American Red Cross has also reached out to Louisiana residents through social media services.
Through its Twitter stream, the Red Cross provided about 1,200 subscribers with updates about evacuation efforts and shelter capacity.
Although its subscriber base is relatively small (some individual Twitterers have a larger base), the Red Cross said those subscribers often "re-tweet" and forward important information on to others in their own network.
"The great thing about [Twitter], is that your message really grows exponentially," said Laura Howe, senior director for public affairs at the Red Cross, adding that the Red Cross also shares information through YouTube, the photo-sharing service Flickr and an online newsroom.
Other social networking services also helped evacuees remain in touch with friends and family.
In an e-mail, Tulane University freshman John Thompson told ABCNews.com that he depended on Facebook to keep track of the new friends that had also fled the city Friday.
To keep its more than 10,000 students abreast of storm developments, the university relied on tweets of its own -- mass text messages with emergency updates.
On the social networking site Ning, a member created a network specifically to aggregate news reports, hurricane alerts, blog posts, tweets, videos and images tagged as a Gustav-related item. Launched in 2004, Ning provides a free platform for anyone to create a network about any topic.
Created with Ning's software, the Gustov Information Center allowed its more than 500 members to not only share information but also conduct online discussions about the areas that were hardest hit, outreach by relief organizations, next steps and other topics suggested by members.
But effective as these online tools were in helping Gustav's victims stay ahead of the storm and in touch with loved ones, they didn't reach large swaths of the New Orleans population.
Blogger Venkat-Ramani acknowledged that the city is notorious for the yawning income gap between blacks and whites and that disparity has carried over to the Internet and social media.
"There's a huge digital divide. Not just racial but also geographic," she said, adding that the blogging community tends to comprise white, wealthier and more educated New Orleanians.
"We've been thinking about a way to reach out to bring in more African-Americans," she said. "It is the next frontier for New Orleans blogging."