Heh, I just heard 4chan mentioned as the source on Erick Erickson's show. lol. Our news media is run by a bunch of rubes who swallow every bullshit story about Trump.
The pissgate story was known about last october by most of the press. The reason they didn't publish anything is because it was uncorroborated. The reason they're saying anything now is because they're reporting the leak <sic> that the meeting Trump had with the CIA etc., included the report of the story being out in the public domain, but that they hadn't established any truth in it. They have to look into any plausible conflicts with a foreign power, especially Russia.
What unraveled was telling anyone that Trump had been told there was a story doing the rounds. The press are doing that story; they are all saying that they have no corroborative evidence to the allegations (Not everyone is spelling those out in detail). They have to otherwise they'll get sued for libel and slander.