I think there is a big difference between the news saying "THIS IS THE GUY! THIS IS THE MONSTER!" and people on a forum speculating that "this may be worth looking into further".
The problem is that all it takes is one group to start quoting the other, and the effect starts to snowball:
"Internet detectives on the popular website Reddit have identified three possible suspects..."
"[Rival news organization] tonight reported on three new leads. The suspects, Joe Bloggs, Susan Smith and Bill Stickers..."
"Ask Reddit - who of the three suspects do you think is most likely to be behind the attacks?"
The problem is that all it takes is one group to start quoting the other, and the effect starts to snowball:
"Internet detectives on the popular website Reddit have identified three possible suspects..."
"[Rival news organization] tonight reported on three new leads. The suspects, Joe Bloggs, Susan Smith and Bill Stickers..."
"Ask Reddit - who of the three suspects do you think is most likely to be behind the attacks?"