Why isnt the FBI letting the news out on the Zodiac?

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apparently some one has come forward last august saying his step father was the zodiac killer.. the FBI has the evidence and is testing it but in september they said they would know any day now.. well its november and i cant find a dang thing on it as far as if its legit or not.. here is the info on the zodiac http://en.wikipedia.org/wiki/Zodiac_Killer here is the most recent news http://cbs13.com/local/zodiac.killer.kaufman.2.805799.html http://cbs13.com/local/zodiac.killer.suspect.2.807424.html and now nothing... i wanna know!! wouldnt the FBI announce it fast if it was to put everyones mind to rest? im guessing if its been this long maybe he isnt really the one.. supposively the "step son" of him has got a bad rep for trying to sell pieces of the victims t-shirts or something to people in the past and a lot of people allege that maybe he just wants to get back at his father for something..