Yesterday we heard, along with a narrator, Zelda speak. I found the trailer to be quite moving even though I've only admired the series from a distance. The direction they are going for is very reminiscent of many Ghibli films, right down to the title treatment and it's reveal. They really nailed the voice work which people have been asking for almost as long as I can remember, which excites me. Here is hoping they'll let you play in Japanese!
But one question still remains: will Link speak?
Edit: I heard the English trailer after making this topic and my feeling only apply to the Japanese voice work. :/