i agree i don't see facebook lasting in the long run, it's already dying and no one even talks about it. The actvity on my facebook feed went down like 90% compared to last year
Facebook will replaced not by one service, but by many smaller services that users will use according to their liking, such as snapchat, instagram, tumblr, twitter, etc.
The reason of facebook's death is their decision to remove privacy settings and constant loss of confidence with surprise changes.
Facebook isn't declining.
http://www.statisticbrain.com/facebook-statistics/
Besides that Facebook simply went from being the cool-hip thing to use for socializing to--something else.
Now its main purpose is to record life/family interacting on a global scale.
Facebook has learned from MySpace, Xanga, and the others who appeared for a year or two just to fade away.
Facebook is here to stay for at least another 10 years, though I predict more like 100+.
Twitter/Instagram/SnapChat/etc all here to stay as well as long as they keep on keeping up.
Snapchat probably won't make it past the next 5 years even.
SnapChat provides a disposable picture sharing service.
Yes, the technology for disposable anything online is still in the baby stages, but it will become of great importance to people as it is to the kids using it.
People want to send temporary pictures over the phone, this won't go away.
Most of the masses that even use SnapChat don't realize how easy it is to still record the temporary picture (they even have apps for it), but that is besides the point.
First people would screen shot the phones.
Now they have methods against that. (alerts the user and shuts the app off)
Now they have apps and ways to get into the device to save the picture.
Methods are being developed that will end this and a new method will have to appear.
It will be an endless fight, but none the less people still want erasable/disposable pictures/information/etc.
//
You can also think of the proxy services, it bypasses your ISP spying on you.
Erasable technology does the same thing, but through any device.
If SnapChat is running inside a virtual machine and thinks it's just running on some normal phone, then there's nothing stopping the host OS from taking a snapshot of the guest OS's state at any time.