The first thing I thought of when I read this was Siri. Unless it becomes much more than it is now, I don't see it as more than a gimmick. If and this a very big if, you could activate it by a word or some kind of voice interaction other than pressing the button on the front of the phone then it would be a step closer to being useful. Right now its just fun to ask dumb questions. Not really that useful. Not when you can do most of the tasks faster just touching the phone. Which you have to do anyway to use it.
I thought the same thing about Siri when I first got my 4S. But the more I used it the more useful it became. It DOES have a nice "Raise to Speak" feature that you just lift the phone to your ear and it launches Siri, no need ot hold the home button. I use it to make appointments (MUCH faster than launching app, going to the date and typing it in), send texts, play music, create notes, add items to lists etc. it's actually quite useful.