I knew of Miku Hatsune virtual singing, but I never knew that games used such a technology too.
I have to say I'd really would like to see this in some MMOs. Of course there would be the spamming problem (as you see in the video), but it could be quite useful in raids, or similar situations. You'd green light your team and then don't have to read what they write, but also don't have to agree on a TS-Service.
It would also be great to read the names, that Players give their character, out loud.
I think it's still not ready to replace actual actors with virtual ones (that could call you by your chosen name), but it could happen in some years.