This article hints Google+ will take over.
Why Twitter is obsolete – Social Media – Macworld
It’s of course silly-simply for Google to copy Twitter from a technical standpoint, considering Twitter is the most basic of services. It’s a whole different thing to copy it’s widespread use.
I’m not sure following is a good thing in Google+, considering a social network system (Facebook) and an information distribution system / micro blog (Twitter) are two very different things. Maybe it’s possible to shut off.