The world doesn’t need saving. It’s been spinning and revolving around the Sun for several billion years, and it will continue to do so for several billion more after humans either move away or die off. The world is fine.
Fluther might save packets of humanity, as has already been pointed out from time to time, and it makes it easier for some parts of humanity to get advice on how to talk to the little red-haired girl across the playground (or conversely, how the little red-haired girl can get the boy to talk to her, or leave her alone, one). First it needs to be able to save itself, though, and the jury is still out on that.
But the world won’t care, and it will just go on spinning and revolving, regardless.