Actually, Facebook and Twitter are why all 7 rapists will be identified. Both companies have found it in their interest to identify the owners of the accounts involved.
Years ago, we wouldn't have had good pictures, from multiple angles of the people we are interested in. Nor, would we have quickly established which Shaw and Telus accounts were used to post the pictures.
I mentioned the Thomas Sophonow case. If you look at the evidence, he was convicted on twine. He was released and made whole because of DNA evidence that wasn't available back then.
The pursuit of justice will never be perfect, however there is much more certainty that we are prosecuting the right people when we have pictures and DNA.
The media coverage, the online discussion, the public awareness have all caused people that would be reluctant to directly speak to law enforcement to identify themselves.
Take you for example, you joined this site and posted twice on this case. You didn't join to discuss pooning, you didn't join to discuss the meaning of life. You joined and posted on this case. That makes you interesting.