> If meta data is concealed, how would the crackers which email is valuable?
From the protocol doc: "When an email is sent then the email’s hash is added to the DHT in the key that matches the recipient’s address; the mail is then transferred in a BitTorrent like fashion."
How does that conceal metadata? If you dont have plaintext From: and To: fields, it doesnt mean the metadata is concealed. Metadata is not whats IN the communication, it is the data that you collect OBSERVING the communication.
Without special measures to provide anonymity, it is no different than an OTR-encrypted chat or PGP email.
As long as it is not possible to crack a proportion of the total traffics, I think it is safer this way.