He doesn't talk, the trailer sells the wrong idea. Which is a shame, the voice over guy in the trailer did a fine job.
I haven't gone over all threads so far, so maybe his muteness is a bug, but I doubt it.
Jakub will probably drop by this thread and answer it clearly soon enough.
Also, on a slightly different note: with so much great art in the game, I'm surprised it doesn't come with a bunch of wallpapers as extras.
it's not a bug. We decided to exclude those one liners, as they didn't sound as good as we wanted them to. We also thought that they didn't meet our expectations.