Is there a way I can use the text-to-speech from the new Google Voice? In Jelly Bean the pronunciation is really smooth so I was thinking may be there is some kind of API fo
Have you tried to use just the standard TextToSpeech class?
See Reference for usage. You can pass a "engine" string to the constructor. If the JB TTS Engine appears as a different engine you could choose it there. But I assume that the new JB TTS engine is used automatically if you just select the standard TTS engine.
Yes, it is possible to access the Google Now voice using the Android TTS APIs. You need to use "KEY_FEATURE_NETWORK_SYNTHESIS" in the "params" parameter for the TextToSpeech.speak() call.
See
http://developer.android.com/reference/android/speech/tts/TextToSpeech.Engine.html#KEY_FEATURE_NETWORK_SYNTHESIS
and
http://developer.android.com/reference/android/speech/tts/TextToSpeech.html#speak(java.lang.String,int,java.util.HashMap)