Seeing as twitter "solves" a non-existant problem ...
... and it does so in a way that existed long before it came into existence, I'd say that it's all in all a redundant waste of time, and has been right from the git-go.
Seriously, first came porn, then came cats. After that came malicious gossip and conspiracy theories. (Sound familiar, twitter users?) And THAT was the BBS world, in the years before it was discovered that UUCP could be used for much the same thing, leading to Usenet ... Face it, twitter has done absolutely nothing for humanity. If it disappeared tomorrow, the world would carry on as if it never existed.