Yes and No.

Perhaps Facebook Really Does Make People Dumber: “typically, Facebook users in the study had GPAs between 3.0 and 3.5, while non-users had GPAs between 3.5 and 4.0.”

I would question, though, what sort of similar results we might get with most technological mediums. As The Dane points out here, the viability and hurtfulness of a medium is determined only by those using it. Just like my huge biceps. I could use them for good or for evil. But if I carry out evil, no one will go around outlawing my huge biceps. (for the record I have nothing close to huge biceps)