Vine is designed to keep family and friends in touch when other communication methods are either broken or not particularly efficient. Times of crisis usually involve a breakdown in mobile phone or other key communication infrastructures, and Vine is designed to be as hardy as possible to keep people connected. Vine can be accessed via a desktop client (Windows only for now), text message or email.
But the value-add of Vine isn't in the social network per se. Fortunately as individuals in the US we don't endure disasters too frequently so a social network dedicated to disaster response is likely to be something that remains in the background for many of us. Which bears the question will people want to maintain a secondary channel in case of emergency? More than likely users will continue to use the social channels they currently use to remain in contact with others rather than switch to another specialized service.
This is exactly what happened last July in LA when an earthquake hit. Cell phones were out (probably because they were taken over by emergency services) but texting still worked. I was at the gym and within a minute of the event (after we evacuated and stood clear of the building) people were able to text friends and family saying they were OK, get information on the earthquake (5.4), and tap into news on any damage or injury (fortunately none). The other day I was on Facebook when 5 of my local LA friends updated their status that a 4.4 quake near Malibu - I never felt it.
My point is that in emergencies people want to connect with the VIPs of their lives, find out what is happening, and share that information. This is nothing new in the world of collaboration and social software, we just step up our activities when something really important happens. What Vine does differently from most social networks is it provides additional value in the form of news and public information combined with the personal network. This is a valuable model that all social networks should ultimately provide; value for the individual, value for the group, and value for the organization.
Mike Gotta has collected some links to articles on Vine if you want to read more.
Microsoft Vine To Connect Family, Friends When Crisis Hits