My kids were just floored when they first experienced the talking Mickey. It was their first ever time meeting a Disney character and I think they were pretty much hip to the fact that characters they'd seen in non-Disney parks were really costumes. I didn't tell them before we went in to meet him and they walked out of the room big-believers in Disney magic.
The tech is really cool and I'm glad to see them expand upon it -- it really sets Disney apart. Kids today are a lot more savvy and suspension of disbelief doesn't seem to be as easy to come by. I find myself a little mesmerized watching Mickey.