Well fb still has the most users, even between 18-24.
I think that tsu will be never able to reach not the activity of Facebook but even 1/1000 of its activity, revenue and users. And this figure is overestimated. Facebook is out and to away of every kind of concurrence in its field of work.
i joined Tsu for some time since his launch before about a year now, it's really new comparing with facebook or even twitter, but its growing too. The sharing method isn't so simple and many users joined only for money and then left after not earning good amounts.
I f it will support Bitcoin, i think its intelligent method to get more members