A friend of mine was at a shuir and the Rabbi was being a total ignorant doofus, and he was talking about how facebook caused a Jewish girl to get engaged to an arab guy.
My friend was absolutely peeved by the accusation, and rightfully so.
The girl clearly didn't care who she was seeing, or who she was with. IF she did she would've stopped herself before anything occured in the relationship. Aside from that there are plenty of websites she coulda met this guy on, eharmony.com, match.com, myspace, or anything else.
These rabbi's need to get reality checks and stop blaming modern technology for their own brain-defects.
There is something VERY wrong in the frum world.