Thanks, Michael, for an illuminating report on some of the GH3's new features, and particularly confirmation that it's IQ seems to be on par with the OM-D's -at least up to the ISO 1600 limit of your early release test body.
As a user of long legacy lenses and apo scope adaptations, I'm particularly interested if you were able to explore several features not mentioned: the new "pinpoint" AF spot as opposed to the GH2's small box; the "silent" (and presumably vibrationless) shutter option; and the new 4X MF mag. assist w/ PIP which should be very usable in handheld birding with the 100-300. The GH2's 7X minimum mag. is just too much without PIP to keep orientation.