Fantastic story. I've been wondering if there is a truly private, easy to use chat. Something cryptographically secure, but easy enough that I could get other family members and friends to use it.
Apple states that they cannot decrypt the data (although they could conceivably tweak that in software updates if desired or ordered to). http://images.apple.com/ipad/business/docs/iOS_Security_Feb1...
> When a user turns on iMessage, the device generates two pairs of keys for use with the service: an RSA 1280-bit key for encryption and an ECDSA 256-bit key for signing. For each key pair, the private keys are saved in the device’s keychain and the public keys are sent to Apple’s directory service (IDS), where they are associated with the user’s phone number or email address, along with the device’s APNs address.
The lack of password recovery could be an issue for some people.