I love the concept of fully spoken dialogue for a fully evolved gaming world, but to be honest, I think in practice it will actually reduce realism.
In Morrowind, every NPC had the same answer for everything, and I think an audio version of this will only magnify the effect, as it will draw more attention to the fact that the characters not only say the same thing, but say it in the same voice with the same tone. In this particular area, I'd agree with Sever and say the more that is left to the imagination, the better.
Not sure if I got my point across properly there, but I've got to be at work in twenty minutes!
