That was exactly my first thought, too - I am still looking further into it though because it does look interesting.
From what I read so far: All parties participating in the mix need to sign off on the payout address. If something is manipulated, e.g. someone trying to divert BTC to anyone other than then intended participants, then at least one party would not sign off on the transaction, and the entire mixing deal would not take place.
So if every participant checks that their receiving address is correct, nothing bad happens ..
Its based on GPG and uses tor .. it does look promising .. and I think I'm gonna try it out because I'm curious
Try it out - but don't stick more than 0.01BTC in it
Honestly, the only safe way to store your bitcoins is offline. Even in the unlikely event the security is perfect, the person running the "system" can always run off with the coins. Happening once every couple of weeks at the moment ..................
Of course they have to claim they have nailed down security concerns. They can hardly say "security - nah, we haven't looked into that yet"