There are definitely certain things that are easier to do with voice, and certain things that are easier by touch. Voice will definitely never replace 100% of interaction, the trick is knowing where it's most useful.

For example, one great example is, sometimes I'm watching something on my Chromecast and I want to skip a very specific amount. I can go "OKG, skip forward 48 seconds". Try doing that with the tiny track bar on your phone precisely...