Focus Numerique, an excellent if minor photography publication online, has posted an ISO comparison of the new Olympus E-M5, and sure enough, its performance is nearly identical to the Panasonic G3. Aside from much stronger default contrast and sharpening, the images are close to identical. The odd gap between the G3 and the Canon G1X at least appears to have been mostly closed with Olympus' superior processing pipeline.
But, and it's a big but, noise, when even measured on a per-pixel level, appears significantly lower on the Sony NEX-7. That is a twenty-four megapixel camera. That is the key problem that these increasingly crappy Panasonic sensors have: the quality of the photosites themselves is far behind the competition. The NEX-5n is nearly a full stop better. That is unacceptable at the price that Olympus wants. Considering the recent results of the new Fuji X Pro 1, with ISO performance that leaves all other APS-C cameras wanting, Olympus needs to move their pricing downmarket, STAT.
As I have reiterated, the weather sealing is a real killer feature for me. As for many people who carry cameras with them at nearly all times, when the rain starts to fall, you either pack it up or enact some ghetto-rig around your camera like wrapping it in a Zip-Loc bag with only the lens peaking out. Less than elegant, to be sure.
Again, I want the E-M5... a lot. It is attractive, elegant, weather sealed, and finally aimed at enthusiasts. If it had been the first camera that Olympus had released, I would be singing a different tune. It would have been a revelation three years ago. But now, it goes up against the soon-to-be-announced Nikon D8000, The Sony NEX series, and Canon doing their own sensor format better than them.
I am begging Olympus to cut ties with Panasonic. Either go whole-hog and actually design their own sensors or buy off-the-shelf units from Sony. Panasonic is giving you its leftovers. This is not real competition. I want this body with a Sony sensor. I want a camera that doesn't require concessions.
P.S. I also want a camera that doesn't have a base ISO of freaking 200.