What do you think about the possible success of a "Sciences Social Network"? We established Sciencia.org as such and get some 1000-2000 submissions of scientific web content per day.
Not sure what to think. But if you are getting 2,000 subs a day - to me, that's pretty good. Especially in a niche like that.
It may be quite effective but it depends on you where do you post? How do you post? How good it is evaluated? So, basically it depends on us how perform over there.