Have you actually listend to the network traffic? It used to be plaintext, so its easy to check, if there is some encryption going on. If there is encryption, then its likly its the one interduced by the TextSecure people.

Why should it be diffrent? What did you expect to change? Thats the good thing about good crypto, the user does not even know its there.

I mean sure, I would like to be able to validate the other persons fingerprint and discover as soon as we are communicating diffrently, but relasticlly, what whatsapp did is the biggest jump in crypto usage since https.