Focus Numerique, a website that I like more with every upgrade to Google Translate, has posted its comparison shots taken with the GH3. They are near-as-damnit exactly what we were expecting for a camera based on the Sony sensor inside the E-M5.
The images posted are OOC JPEGs, but they also provide RAW files which can be easily and quickly dropped in Raw Therapee for deeper analysis. As expected, the JPEGs give the edge to Olympus at everything above ISO-800. The Oly manages to extract better everything from the data, but the extreme voodoo being applied sometimes causes images that look inferior to the GH3, so it isn't a complete a win for Olympus.
Moreover, once we view the files in RawTherapee, the differences become, at least as far as I can tell, academic. I think that the Olympus is still doing better, but even in RAW, the GH3 seems to be superior in some areas of the shots. I think that is all beside the point. I think that the real point is that the GH3's sensor is not a downgrade from the E-M5, which I, and many other people, were worried was going to be the case. Aside from the GH1 and to a lesser degree the GH2, Panasonic's cameras always had inferior image quality to Olympus' implementations of the same sensors, and both of them were significantly inferior to Sony's sensors.
Aside from the IBIS, the GH3 is lacking nothing in comparison to the E-M5 and brings many more goodies to the table. While better images than the Oly would have been some excellent icing on the cake, I can't be anything but satisfied with these results.