Professionally I never use manual focus. However, I do attach a rather expensive Marshal 7" external HD monitor in order to judge critical focus. Tiny LCDs are no match, and as a crutch, some models will use peaking, a form of visual oversharpening on the LCD to let the user know whats in focus.
Holding out such a camera at arms length would be awkward, especially when trying to use one hand or finger to adjust focus manually. Even a medium sized lens not usually requiring a tripod would be forward heavy with arms extended.
You would have to cup the camera in your left, using thumb and forefingers to work the lens while balancing with the right. It would be interesting to know if stabilized lens would provide assist or be feature locked.
Still, better than not having video and one could adapt it, but certainly not replace their dedicated video gear with it... yet (at least not a first generation unit).