(Currently I see the same thing happening with the Bitcoinica scam - given the evidence I cannot understand why these guys (esp. Zhoutong) are not scammer tagged (instead theymos chose to accept 80 BTC from Zhoutong to advertise his next "project" 
- filling all available ad slots of the forum. https://bitcointalk.org/index.php?topic=94475.20))
- filling all available ad slots of the forum. https://bitcointalk.org/index.php?topic=94475.20))Ever hear of reasonable doubt? Innocent until proven guilty? There is no solid proof it was him, and marking him as a scammer if he's innocent would open up the forum to serious legal problems (and rightly so).
This is probably not the right place to discuss this.
I know about presumption of innocence. Thanks for the special instructions.
However there is substantial evidence in the ZT case: https://bitcointalksearch.org/topic/public-statement-regarding-bitcoinica-account-hack-at-mtgox-95738
Since scammer tags have been issued in less severe cases of equivalent certainty in the past it is not disproportionate to issue scammer tags in the bitcoinica case.
At the very least forum operators should not engage in dealmaking with probable scammers, effectively helping them to run the next (unprovable) scam.
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