We will open up the beta hopefully this weekend we are currently alpha testing among the core team getting the last few issues out! We should be ready for a full public launch by December 1st! Our goal with Shadow Chat is verifiable and ability to have encrypted chat. You can prove who said what when where and why just by a key! WHY is this not already implemented on the "official steemit chat"? We have no idea! But that is why we are creating it! The whitepaper very clearly outlines the memo key is used for signing memos which are another word for messages. Chat can therefor be thought of as a bunch of memos trading back/forth on the blockchain. ALL signed and some encrypted. We will release later this week a full detailed explanation for Shadow Chat.