I think this is a great idea and would do a lot for the interaction between kids and characters. Often times kids, little ones especially, are terrified by the fact that there is a big, mute, character looking at them with a blank unmoving stare. To have the characters face move and blink and to hear their voice telling them its okay, would do wonders for the experience. I know my 3 year old would have a cow if Mickey called him by name and wanted to be his friend. I hope this becomes the norm soon, its a great technology that moves the character interactions into the 21st century.
In the future they could move the face character meet and greets outside and then have the Mickey and the gang move to indoor locations to utilize this technology.