I still want Voice integration. I don't use SMS since I decided not to get scammed anymore. Voice would be awesome.
I wonder how the transition will work for the public. Do they see their Messages app just disappear? How would they know the SMS app is now integrated into Hangouts? Assuming an OTA 4.4 update to a Nexus 4.
They would probably put it where it their Messages app would be or some sort of alert to let people know.