I just came across http://www.pchood.com/USB%20Follow%20Focus and as I'm using the Olympus 14-35mm 4/3 lens it would be very handy to control the fokus with a device like this. The Olympus has a quite good focus motor and a mechanical FF is sometimes not the best solution (e.g. on a steadycam you don't want a mechanical FF).
Vitaliy, do you think it is possible to enable such an option for the USB port on the GH1/2?
If such an option is not present in the camera software at all, that would be to much to rewrite it - but maybe this function is already there in a service mode. Most cameras can be controlled via USB for testing in factory or when send in for repair. So, all that might to be done is enable this function in normal user mode (and of course get a device like in the link which can controll GH-cam).
So I will have to design an built a focus mechanism for my steadycam that will be: -> mechanical via gear(ring) on the lens driven by an electromotor -> motor controlled electronically by a knob (similar to something like in the link but all DIY).
I'm even thinking of going wireless - but thats not going to be easy.