User blog comment:Pihou/VOCALOID 4 Predictions?/@comment-32500188-20140711234915

For the software itself: I forsee the incorporation of a better vibrato/pitch-bend system (similar to what's seen in UTAU or Vocalistener), or Vocalistener made into an actual built-in function of the main editor. My wishful thinking also hopes that there would also be more room for extra VSTs slots and recording input from keyboard/MIDI controler directly to the V4 editor...

As for voicebanks... extra "secret" phonemes/transitions that aren't usually included with a given language. It'd be nice for more Vocaloids to have those options like MAIKA in order to make being able to mimic other languages a lot easier. I'm also hoping V4 would be the generation to bring in more new male Vocals for the available languages. (I'd love to see a Chinese or Korean male hit the scene. :-3)