I am little baffled by this Siri malarky...voice recognition has been around since god knows when! In fact according to my good friend Wiki, it has been around since '52. And in phones since for as long as I can remember.
Question you gotta ask yourself is how many times have you EVER used voice dialling on your phone?
(Granted - Siri is an evolution of this tech, but I would still never use the thing.)