Is the GH3 shutter silent only with slow speeds?

That's a very lucid reply from Bob. I also didn't get why the previous poster seems to consider that DSLR's already have this feature at all, let alone in its ideal realisation. All DSLR's in live view mode are well behind any of the m43 cameras. Even if they had an electronic shutter, the mirror would still have to be moved out of the way and that would create some noise.