I think it's a bit too soon to be saying auto-focus isn't required on a professional video camera. We need to see what the autofocus is capable of first. Purists don't need to get the upgrade or can set the focus to manual if it keeps them happy. I expect autofocus will be a big selling point for low budget productions and one person companies.
Absolutely correct. And I might add that when I work on a full fledged video job I use cameras better than C100. C100 is aimed at productions with limited budget and in this case this feature is super welcome. Even for documentaries... Lets see what future holds..