It's actually quite amusing how controversial this topic is, especially since the people against it all seem to say the same thing: "LINK SHOULD NEVER TALK!" Come on, people, Nintendo would never make Link talk. That goes without saying. A Zelda game with voice-acting wouldn't automatically make Link talk. Just look at Jack and Daxter and Metroid Prime 3. The protagonists never talked the whole time. Only the NPC's talked, and it worked tremendously. What would make Zelda so different? Nothing. All that talk of "ruining Zelda's individuality" is bogus. Yes, I flat-out said that. Because it is. Zelda isn't the only series that some fans didn't want voice-acting in. I'm sure Metroid fans didn't want the characters to talk for the same reason Zelda fans are. Yet look at the success it had with it. Zelda wouldn't be any different. Voice-acting brings dialogue alive and allows the true emotion of the words to be brought out. While the "grunt style" does just fine with that, voice-acting does a bit better of a job with it.
Now, hear me out on this. I don't want voice-acting throughout an entire game. There's way too much text in Zelda games for that. All that would do is slow the game down. All I want is voice-acting in the cutscenes, and for two major reasons. First reason, the cutscenes are detached from the gameplay. They're meant to be watched and enjoyed, not played. They're the sole moments in the game where we have absolutely no control of what happens. Voice-acting would feel intrusive in the cutscenes because of that. We're already don't control anything at those points, so any kind of arguments about the dialogue being slowed down don't hold much water, and the cutscenes would come alive more than ever and feel more natural. (Of course, I would never want Link to talk.)
The second reason is in some ways the complete opposite of the first reason. When the cutscenes are not rolling and we're back in control of the game, I'd rather there be no voice-acting. Instead, I want the "grunt style" to come back in. Part of this has to do with not wanting these parts of the game to be slowed down, but the major reason is because I just don't want that unique style to be completely phased out. When there aren't any major events that need to take place in a cutscene going on, there's less focus on the emotion in characters and more on what our next goal is. This is where that "grunt style" can really shine. The over-exaggerated movements and sounds coming from the characters is always entertaining to watch when making normal conversation with them. In the more relaxed feel of these moments, I feel voice-acting would feel a bit out of place. I'll give an example.
In Skyward Sword, just after the scene where Groose followed Link and crash-landed with him in Faron Woods (followed by a freak out), the game goes back to normal gameplay with Groose basically giving a recap of what's supposed to be done, only in a way that focuses on him rather than the main quest. At that point, him talking just wouldn't feel right. Those grunts and over-exaggerated facial expressions provided a more relaxed feel, which was perfect in that situation. While there are plenty of other examples, each of which are quite different in reasoning, I think that's all I need to get my basic point across. The main point is I want voice-acting in the cutscenes to bring them to life like never before, but to keep the "grunt style" in the other portions of the game to prevent the game from feeling slowed down and to keep that unique and entertaining style of communication in the series, as it really fits quite well. I really hope Nintendo does this sort of thing in the future. Whether or not they choose to use a universal set of Japanese voice-actors speaking in Hylian or have each area provided with dubbed local languages or not would be up to them, but I'd prefer it to be in Hylian. That would give the game a more authentic feel of being in Hyrule. Either way I'm good with. But my preference would be Hylian. (And, of course, I still want the text boxes to remain in the series.)
I can't even stand what Nintendo has done in recent titles with the mouth-moving to indicate speech. It just... bothers me.
Yes, I feel the same way. Most of the cutscenes in Twilight Princess felt sort of empty without words coming out of the characters mouths. I mean, the movements were following the words. Then Skyward Sword did something that was just plain awkward: have the mouths move up and down. That didn't fit very well at all. Thankfully, it wasn't used throughout the entire text most of the time, so it didn't create a sense of, "Dang, this is just embarrassing," but it still felt awkward at times. If Nintendo's going to do this mouthing stuff, put the voices with it. It just doesn't work properly without actual voices, especially the simple up and down movements.